DST start and end dates

[markp201]

We're having to adjust UTC to local time for historical data so I needed a way to determine if the date is DST or not.

DST starts on the 2nd Sunday in March and ends on the first Sunday in November.

I tried this out with 2016, 2017 and 2018.  Seems to hold but will likely create a load script to verify.

Also, DST changed back in 2007 so this only holds 2007 going forward.

//Start of DST for current year

DATE(MakeDate(YEAR(NOW()),3,1)+(6-WEEKDAY(MakeDate(YEAR(NOW()),3,1)))+7) & chr(13) &

//End of DST for current year

DATE(MakeDate(YEAR(NOW()),11,1)+(6-WEEKDAY(MakeDate(YEAR(NOW()),11,1))))

//Start of DST for historical date

DATE(MakeDate(YEAR([Field]),3,1)+(6-WEEKDAY(MakeDate(YEAR([Field]),3,1)))+7) & chr(13) &

//End of DST for current year

DATE(MakeDate(YEAR([Field]),11,1)+(6-WEEKDAY(MakeDate(YEAR([Field]),11,1))))

This is not perfect since some states do not observe dst so feel free to post modifications or maybe there is a simpler method.

[markp201]

Test results