Thus the "weekdays" involved in the calculation of days1 are 1-2-3/4/5, where / indicates the counted boundaries. I have code that, via the intck function, calculates the number of days between to dates. ; format TS datetime20. Here is the first step where we are. The time unit can be selected in years, months, weeks, days, or whatever you feel like. sas. Now we set up a custom interval which we'll simply call "workdays". SAS is headed back to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. (To convert the SAS date value to a calendar date, use any valid SAS date format, such as the DATE9. 03 -5 15 0. I think you need to include both activity_date and send_date - the date version not the datetime - in your GROUP BY, to avoid your data being re-merged. Hai Kuo, Thank you for providing the code. ①結果自体は、SASテクニカルサポート「年齢の計算方法」にあるやつと同じになる。. So, INTCK works only with SAS date values, such as '01JUN2019'd, or integers representing days from Jan 1, 1960. Consider the following examples: Using INTCK and INTNX. proc setinit; run; And what's installed on your system using: proc product_status; run; The output will be in the log. Make sure to include you grouping variable in the output dataset, otherwise the data will be difficult to interpret. The function INTCK ('MONTH','31jan1991'd,'1feb1991’d) returns 1, because the two dates lie in different months that are one month apart. The INTCK function using the default discrete method counts the number of times the beginning of an interval is reached in moving from the first date to the second. You need to apply a format to the date value so it displays properly. You can create multiples of the intervals and shift their starting point. This function uses the following basic syntax: lag1_value = lag (value); By default, lag finds the previous value of some variable. However, when SAS provides a function, most likely it is more efficient than code we would write, plus INTCK doesn't care whether the date variable is seconds, minutes hours, days, etc. "as is" without warranty of any kind, either express. “alignment”: It controls the position of SAS dates within the interval. com. SAS will attempt to convert strings to numbers or vice versa for comparisons but the macro variable AS FORMATTED can't be converted. sorry to ask like this but any help please. What is INTNX and INTCK in SAS? SAS programmers rely on INTNX and INTCK functions to manage date intervals. Basically, we had to apply one of two formulas to compute variable right_hours_slept: (wake_time-bed_time)/3600 if bed_time is "at or after midnight. ODS and Base Reporting. dob, doe); RUN; Right now if I had the date Oct 1, 2007 and Nov 15, 2011 it gives me 49 months I want it to give me 49. So if you want to calculate minuates by yourself you need to divide by 60. It does not. You can use the optional alignment argument to specify the alignment of the date that is returned. The approach is to first calculate the number of completed months. calculating number of months between birthday and current date using following expression: You can use the INTCK function in SAS to quickly calculate the difference between two dates in SAS. The SAS code for the INTCK implementation using PROC SQL is presented in the Appendix of this paper. com. Here, the start date is b_date, the end date is wt_date1, and the time interval is 'year'. Every single function in a %LET needs to be wrapped, including your INTCK () and MDY (). If both the anndats variables in each dataset are date type (not date time) then you can simple do an equals. The intervals can be used as arguments to the INTNX and INTCK functions. ). You will have to create a new variable in DATA step creating a new data set. Example 1: Sort Observations Ascending. BEGINNING (B) : returned date value is aligned to the beginning of the interval. They take the data variables as arguments and return the result which is stored into another variable. You could of course also just paste your existing SQL code into a pass-through SQL block and send it directly to the database. You can use sas function intck to find required interval. The sample code on the Full Code tab illustrates how to determine a person's current age using their date of birth. By using multipliers and shift indexes, you can create multiples of intervals and shift their starting point to construct more complex interval specifications. Difference between INTNX and INTCK functions. Example. They can be used for calendar calculations with SAS date values, to count time intervals between dates, and to increment dates or datetime values by intervals. BAN) AS COUNT, CASE WHEN COUNT (A. Grouping Results by Value Ranges. However, most cultures observe certain non-productive days that they call "holidays", and this use of the INTCK function does not consider these when discounting the total sum of days. The SAS INTNX function consists of 4 arguments of which 3 are obligatory: interval: a character constant, variable, or expression (in lower or uppercase) that specifies your interval, e. To calculate current. Often stock price analysis is done that involves comparing daily close to next daily open. Interval – can be in minutes, seconds, hours,weeks, days, months,quarter and year Start_date and end_date are between two dates which we will be finding interval; So we will be using EMP_DET Table in our example. The macro is used in a SAS DATA step as follows: age = %age (somedate,birth); For example, the following lines: age = %age ('28aug1998'd,'24mar1955'd); put age=; will cause the following message to be placed on the log: AGE=43. SAS provides some powerful date functions. You need to wrap your functions in %SYSFUNC (). Please identify the non-numeric type data first and change it to numeric data type using format yymmdd8. SAS のINTCK関数を使用すると、SAS の 2 つの日付の差をすばやく計算できます。. These functions are used as part of the DATA statements. Aligning SAS Date Output within Its Intervals. Try/Buy SAS Viya. However, to use the function you need to convert your 'date' into a SAS date within the quarter. If you are performing a calculation such as age, or tenure, then be sure to use the 'continuous' parameter of intck(). Looks like your time stamp values are numeric variables with datetime values. 4 Functions and CALL Routines: Reference, Fifth Edition documentation. 1. So just take the difference and apply the TIME format to have the number of seconds print in the tradition HH:MM:SS style. In your first example 14Nov2021 to 24Jan2022, this crosses two month boundaries (1 Dec 2021 and 1 Jan 2022) so RESULT1 = 2. 1. INTCK function created identical values except for the dates with DEC 31. SAS is headed back to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user. is a value that represents the number of days between January 1, 1960, and a specified date. Specifies one or more interval name-value pairs, where the value is a SAS data set that contains user-supplied intervals. SAS/IML Software and Matrix Computations. Re: Difference between quarters. INTCK Function. To recap:-- LAGn is a queue of N items in memory occupying <item length>*N bytes. . com. The optional method argument specifies that. , INTCK returns a value of 1 even though only one day has elapsed. ),yymmdd8. Closes SAS data set after it has been opened by the OPEN function. Sample. Y2. date1 = day (date): Returns the day of month from the variable date. I ask this because, for a company whose fiscal year ends in (say) october, then the quarter difference between Jan (end of fiscal Q1) and Feb (start of fiscal Q2) is 1. The INTNX function helps you compute the date that is 308 days away in the future from a specific date. 3 in decimal arithmetic. The INTNX function advances the date or time values by a given interval and returns a date or time value. Well, I have a table with 66'814 observations of start and end dates and I need to get only the weekdays. RUN_DATE AS REPEAT_DATE,COUNT (A. CAREFUL: Results may surprise you (off-by-one problems). For SAS newbies, this video is a great way to get started. The function INTCK ('MONTH','1feb1991'd,'31jan1991'd) returns –1 because the first date is in a later discrete interval than the second date. I'm hoping to find out which of these calculations represents the true age at vacc. mmm. ,&date_end. SAS stores datatime values in seconds. SAS® Viya™ 3. Discussion statsINTERVALDS= System Option. The INTCK function works both with time variables and datetime variables. And further, need to get all intermediate months between those two min and max date in a new column. Note: This is Example 6. Specifies one or more interval name and value pairs, where the value is a SAS data set that contains user-supplied holidays. DataFrame #. conversion-type. The INTFIT function returns the most likely time interval based on two dates, datetime values, or observations that have been aligned within an interval. The SAS intck function computes the date and time intervals for the two different dates, while the INTCK function varies on the time units. sas日時値で使用する必要のある間隔は、sas日時間隔です。 The INTCK function counts the number of interval boundaries between two date values or between two datetime values. SAS® Visual Data Mining and Machine Learning 8. The INTCK function returns the months between &start_dt and. You will need some sort of calendar for this. Week 0 means that the first day of the week occurs in the preceding year. SAS® 9. The INTCK() function will count the number of boundaries crossed. For example: data have1; The INTCK function using the default discrete method counts the number of times the beginning of an interval is reached in moving from the first date to the second. I have tried the below, however it does not populate anything. The INTNX function returns the SAS date value for the beginning date, time, or datetime value of the interval that you specify in the start–from argument. You can use the INTCK function (SAS speak for Intervals - count number of) to calculate the number of quarters from the base date. INTCK(‘WEEK’,’01JAN1960’d, ’04JAN1960’d)=1 01JAN1960 is a Sunday, so the week counter is triggered because default WEEK starting point is Sunday. Hi Experts, please help me to find a max and a min date value from 10 date fields (date1, date2, date3. ) The following example shows how to determine the date of the start of the week that. x=intnx ('week', '17oct03'd, 6); put x date9. The values BEGINNING, MIDDLE, or END align the date to the beginning, middle. %LET dateend=SYSDATE9; %LET newday=%SYSFUNC(INTNX ('day',"&dateend"d,-1)); I set the first macro variable called dateend to be the current date, then. intck(): 'day' for SAS date values, 'dtdate' for SAS datetime values. specifies the year of the later date. The sample code on the Full Code tab illustrates how to determine the exact number of years, months, and days between two SAS date values. Details. As an example, most of the time, a calendar month is not exactly thirty days long,The INTCK function in SAS can calculate the difference between any two dates or datetime values, and return whatever interval you're looking for (days, minutes, hours, weeks, months). In this case you would need to adjust the argument ('QTR') in intck ('qtr',begdate,enddate). documentation. I want get number of day difference between that date and date of today. SAS Web Report Studio. Use the SAS DAY() function here. The input variables required for INTCK are date time, time or date. happens to be February, use INTCK function to decide whether the event occurred on a leap year. On line 144 you are using : types {i}=put (toWatt (max_power {i}), w. intck() returns the number of interval boundaries. Customer Support SAS Documentation. Valid in: Configuration file, SAS invocation, OPTIONS statement, SAS System Options window. 1 Functions and CALL Routines: Reference documentation. Anniv = intnx ('year', '30APR1789'd, 7, 'same'); returns the 7th anniversary of the date 30APR1789. INTINDEX Function. This videos doesn't just explains HOW TO INTCK FUNCTION to get the DIFFERENCES BETWEEN TWO DATES, TIMES AND DATETIMES but also EMPHASISES ON HOW YOU CAN GET. An Introduction to SAS Viya Programming for SAS 9 Programmers. Try/Buy SAS Viya. If the argument's value is within 1E-12 of an integer, the function results in that integer. 11 from Combining and Modifying SAS Data Sets - Examples. DATETIME values are seconds. Find more. The following example shows how to use this. Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. INTCK( 'datetime-interval', datetime1, datetime2 <, 'method'>) returns the number of boundaries of intervals of the given kind that lie between the two date or datetime values. The function can use a character constant, a variable, or an expression that contains an interval name, and can use a discrete or a continuous method to measure time. The INTNX function increments dates by intervals. What is the 'neatest' way of resolving this issue? data _null_; x="01APR08"d; y="28APR08"d; z=intck('MONTH',x,y); put z= ; run; EDIT: response to Martins comment. Thanks a lot for your reaction! What I try to accomplish is the following: I have a dataset that has monthly observations for the following variables from CRSP (i. To analyze data with the SAS System, data values must be stored in a SAS data set. The variables are named start_date and end_date. In the following example, the DATDIF function returns the actual number of days between two dates, as well as the number of days based on a 30-day month and a 360-day year. 1 Answer. Two of my date variables are numeric in MMDDYYYY format. )); /*Here we have a problem and we. SAS® 9. Second your actual dates do not match the values you posted. SAS Date, Time, and Datetime Functions. 4 DS2 Language Reference, Sixth Edition documentation. However, clearly this is not the case as NumMondays=4 in the code above. BKD_DT, 1, "B") - t1. com SAS® Help Center. Working with User-Defined Formats. But perhaps you just want to take the difference between the year number, independent of when in the year the date was. Interval: It can be set as ‘year’, ‘month’, ‘week’, ‘weekday’, etc. Interval Functions INTNX and INTCK Lags, Leads, Differences, and Summations Transforming Time Series Manipulating Time Series Data Sets Time Series Interpolation. They can be used for calendar calculations with SAS date values to increment date values or datetime values by intervals and to count time intervals between dates. I'm trying to count the number of each days for the current month. Graphing Your CAS Output. Accessing Data. is an arithmetic or logical expression to evaluate. Re: Use INTCK in open code. YEAR - Given a number or a variable representing a date or datetime, returns the year. shift-index >. Posted 08-21-2018 08:17 AM (1803 views) | In reply to AMFR. . Improve this answer. Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. com The paper covers setting up base SAS to do date calculations based on business days. start=21JUL2017:09:06:00. Sorted by: 2. INTRR Function. The paper walks through creating a business day interval and working with intck and intnx to count and increment dates based on business days. Now, review the assignment statement that is used to calculate the values for the variable days_intck. ) The following example shows how to determine the date of the start of the week that. data test; date=intck. m36 such that each column has information about a status for that given month. You can create a SAS date value with the MDY function. g. New SAS User; SAS Software for Learning Community; Ask the Expert; SAS Certification; SAS Tips from the Community; SAS. shift-index>. In your SAS program, include a FORMAT statement that is associated with the begin variable that specifies a SAS date, datetime, or numeric format that matches the begin variable data. diff_months_cont = intck ('month', mydate1, mydate2, 'C'); run; If you set the method argument equal to ‘C’ when you calculate the difference in months, SAS calculates the number of complete months between two dates. @dgammon shares this example of using INTCK with datetime variables to calculate a day interval. INTNX () is basically used to get the future or back dated date with a gap of given specific intervals like MONTH, WEEK, YEAR etc. INTCK( 'date-interval', date1, date2) INTCK( ' datetime-interval ', datetime1, datetime2 ) returns the number of boundaries of intervals of the given kind that lie between the two date or datetime values. INTNX Function. It does not count the number of complete intervals between two dates. 4 Functions and CALL Routines: Reference, Fifth Edition documentation. From the documentation, the SAS intnx() function takes 3 arguments, ‘interval’, ‘start-form’, and ‘increment’, with an optional fourth argument ‘alignment’. Re: Nested SYSEVALF Errors in Macro. , INTCK returns a value of 1 even though only one day has elapsed. If only one value is listed, then the COALESCE function returns the value of that argument. diff_months_cont = intck ('month', mydate1, mydate2, 'C'); run; If you set the method argument equal to ‘C’ when you calculate the difference in months, SAS calculates the number of complete months between two dates. Try/Buy SAS Viya. intnx関数について基本の話. I'm not sure how to make my own intervals. The form of an interval is. 1 関数とCALLルーチン: リファレンス documentation. name < multiplier >< . mmm. Try this: SAS now counts complete months. Time is stored as the number of seconds since midnight. Aligning SAS Date Output within Its Intervals. 24567: Calculate a person's age. intckは、スパンではなくデルタをカウントしますが、デルタとスパンの差は常に1です。 日付間隔と時間間隔の操作の詳細については、日付間隔と時間間隔を参照してください。 日付間隔と日時間隔. The COALESCE function checks the value of each column in the order in which they are listed and returns the first nonmissing value. sas. If only one column is listed, the COALESCE function returns the value of that column. D. If neither expression is true, then the compound expression is true. com The INTCK Function in SAS (real-life scenarios) The INTCK function can be used in multiple scenarios but here are those are on top of my mind where it can be used extensively: 1. There are three parts to translating: INTNX ("MONTH", t1. SAS Forecasting and Econometrics. If SAS reads Y with a different informat, or if a program other than SAS reads Y, then there is no guarantee that the characters "0. The function INTCK ('MONTH', '31jan2013'd, '1feb2013’d) returns 1, because the two dates lie in different months that are one month apart. INTFIT Function. SAS is headed back to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS. For more information about working with date and time intervals, see Date and Time Intervals. INTNX shifts a date by a specified interval, while INTCK computes the intervals. The interval can be used as an argument to the INTNX and INTCK functions. ); 3) The most simple way to convert the input to a sas date - which maybe you used is:James Harroun walks through the process using SAS Studio for SAS OnDemand for Academics, but the same steps apply to any analytics project. We are going間隔とは、日、月または時間などの経過期間内でSASが計測する測定単位です。. The INTCK function using the default discrete method counts the number of times the beginning of an interval is reached in moving from the first date to the second. dd. FROM Customers t1. Date extraction functions are used to extract a portion of a date from a date variable. SAS Functions and CALL Routines Documented in Other SAS Publications. Difference between INTNX and INTCK functions. SAS® Viya™ 3. However, a little tweaking is necessary to get exactly what we need. It covers a wide range of base and advanced tutorials that will help you get started with SAS. The intervals involving the date portion of a datetime variable in the Intnx or Intck functions start with DT, such as Dtday, Dtmonth, Dtquarter, Dtweek, Dtyear. sas. The age computation takes into account leap years. 2: DS2 Language Reference. Thanks, Jag View solution in original post. If the value of argument is negative, the INT function has. SAS® 9. 3. Example. SAS® Help Center. 000 stop=23JUL2017:10:28:00. date1 = today (): Returns today's date as a SAS date value. The INT function returns the integer portion of the argument (truncates the decimal portion). 0 false 1 true . We can use the INTNX function to create a new column called firstmonth that contains the first day of the month for each date in the date column: /*create new dataset with column that contains first day of the month*/ data new_data; set original_data; firstmonth=intnx('month', date, 0); format. INTCYCLE Function. --INTCK(interval,start-of-period,end-of-period) is an interval function that counts the number of intervals between two give SAS dates, Time and/or datetime. date1 = month (date): Extracts the month component from the variable date. . ) The following example shows how to determine the date of the start of the week. Looks as though you're using the explicit pass-thru access to TD, so you're limited to the TD=specific SQL syntax which, obviously doesn't support SAS functions like INTCK. sas. To the macro processor everything is text, so quote characters are just part of the text. EDIT: If you add the continuous option then the results change. The 5-digit results you see are correct, a SAS date is the number of days since Jan 1, 1960. In this SAS tutorial, we will show you how to learn SAS programming on your own. Maxim 3: Know Your Data. If you accessed TD via a LIBNAME engine, INTCK would work, as the function would be invoked on the SAS' side after having the TD date translated into the SAS date. AIRY Function. Calculations can use months and years that contain the actual number of days. Two for the price of one - here is a solution using a lookup table (as a SAS informat) assuming your data is not. Analytics. Analytics. SAS Help Center: INTCK Function DS2 Language Reference INTCK Function Returns the number of interval boundaries of a given kind that lie between two SAS dates, times, or. SAS determines date and time intervals based on fixed points on the calendar or clock. SAS Interface to Application Response Measurement (ARM) Security. Here is the first step where we are. 間隔計算の開始点は、デフォルトで開始値が入る期間の開始時点となります。. It does not count the number of complete intervals between two dates: The following example returns 0, because the two dates are within the same month. It does not count the number of complete intervals between two dates: The following example returns 0, because the two dates are within the same month. %SYSEVALF ( expression <, conversion-type >) expression. yy or yyyy. 3" would produce a value of exactly 3/10. The SAS code for the INTCK implementation using PROC SQL is presented in the Appendix of this paper. Once you convert the date, you can find the number of days between the two dates with the INTCK function, and then subset the table appropriately. 2' et al) (and I've never personally had a reason to use them), I'll keep on using arithmetic,. INTNEST Function. Dates before January 1, 1960, are negative numbers; dates after are positive numbers. You will need to demonstrate now SAS is returning a non-integer value from the INTCK function with MONTH as the first argument. The function cannot be a macro function. The default is “DISCRETE” but you can specify if you want to use the “CONTINUOUS” method. For example, the INTCK () can be used to determine how many months to generate. The default method is month boundaries so intck ('month', '30jun2015'd, '01jul2015') will count as 1 month as a boundary has been crossed. 4 関数とCALLルーチン: リファレンス、第5版 documentation. When you use date and time intervals (for example, with the INTCK or INTNX functions), SAS bases its calculations on the calendar divisions that are present. Sample. I can do this with SQL, but is bad for performance and does not run on large data sets. Use them with the INTCK and INTNX functions and with procedures that support numbered lists (such as the PLOT procedure). Especially when trying to find newborns where age is less than 1. The syntax is very similar to the INTNX function, INTCK(interval, from, increment, alignment). g. The function INTCK('MONTH', '31jan2021'd, '1feb2021’d) returns 1, because the two dates lie in different months that are one month apart. Thanks. The INTCK function returns the number of intervals between two date values. %let dsname=MAY2019; %let start='01MAY2019'd; %let end='31MAY2019'd; create table &dsname. 1. Fast forward more than four decades later, and SAS has thousands of employees and customers in locations worldwide, analyzing billions of rows of data every second that are changing how we live. If the value of argument is positive, the INT function has the same result as the FLOOR function. SAS® 9. sas. The INTCK function returns the number of interval boundaries that lie between two SAS dates, times, or timestamp values. The INTCK function in SAS returns the number of interval boundaries that lie between two SAS dates, times, or timestamp values. The COALESCE function checks the value of each argument in the order in which they are listed and returns the first non-missing value. since intervel is. Moving and Accessing SAS Files. INTINDEX Function. CAS Action Programming with CASL, Lua, and Python. 1582 to A. The INTNX function returns the SAS date value for the beginning date, time, or datetime value of the interval that you specify in the start–from argument. Analytics. SAS determines date and time intervals based on fixed points on the calendar, the clock, or both. Hi ballardw. Explanation. Syntax of INTCK function: INTCK(interval , start-date-time, end-date-time, <'method'>) method: – It’s an optional parameter. ); format date1 date2 yymmn6. Feb 29 is. INTCK function Examples. Returns the current date as a numeric SAS date value. 2: DS2 Language Reference documentation. SAS is headed back to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS. Date difference using SAS INTCK Posted 07-21-2021 01:40 AM (922 views) Hi, I am calculating difference in days between diagnosis date and first lab test date using intck, but my code is not working right. @dgammon shares this example of using INTCK with datetime variables to calculate a day interval. SAS is headed back to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. (INTCK returns a negative value whenever the first date is. Third point - shrug. (INTCK returns a negative value whenever the first date is. SAS is headed back to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. SAS® Help Center. SAS Data Science. Customer Support SAS Documentation. INTCK( 'datetime-interval', datetime1, datetime2 <, 'method'>) returns the number of boundaries of intervals of the given kind that lie between the two date or datetime values. Glad to be able to help 🙂 When calling DATA step function from MACRO using %SYSFUNC, the general rule is to always leave out the quotes. Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. The INTNX function returns the SAS date value for the beginning date, time, or datetime value of the interval that you specify in the start–from argument. 5 Programming Documentation. The following. In SAS, you use the INTCK function to calculate the difference between two timestamps. (To convert the date value to a calendar date, use any valid DS2 date format, such as the DATE9. It can be year, month, week, or weekday. SAS® Visual Data Mining and Machine Learning 8. If "to" is before "from", the function returns a negative value. If the argument's value is within 1E-12 of an integer, the function results in that integer. But perhaps you just want to take the difference between the year number, independent of when in the year the date was. The INTCK function using the default discrete method counts the number of times the beginning of an interval is reached in moving from the first date to the second. The Basics. INTNEST Function. People often ask how to use SAS to calculate the leap years. data test; date=intck ("month",'01FEB2021'd,'31JAN2022'd,'c'); run; The SAS interval functions INTNX and INTCK perform calculations with date, datetime values, and time intervals. The function INTCK ('MONTH','31jan1991'd,'1feb1991’d) returns 1, because the two dates lie in different months that are one month apart. If the value of argument is negative, the INT function has. In addition the date values can also be aligned to start, mid or end of given interval. Posted 06-19-2016 02:35 PM (12054 views) Hi , I need to calculate age at graduation. SAS can perform calculations on dates ranging from A. I want to calculate the month between 01FEB2021 and 31JAN2022, but even with the continous option the result is 11 month. )) as MONTHS. 結果データセット「AGE2」. Learn how to use the INTCK function to calculate the number of interval boundaries of a given kind that lie between two dates, times, or datetime values. If SAS reads Y as the characters "0. But as written earlier you should avoid using SAS functions for data base tables which SAS can't push to the data base for execution. To start set the values manually. I'm trying to group those results into range buckets using 1 - 5 days, 6 - 10, days, 11 - 15 days, 16 - 20 days, 21 - 30 days, and 30+ days. INTFIT Function. ) The following example shows how to determine the date of the start of the week. Dates before January 1, 1960, are negative numbers; dates after are positive numbers.