loop based on a condition

[jb9977]

I have a dataset
FiscalDate    year    Value
01JAN2012   2012     2
14JAN2012    2012    3
15JAN2012    2012     4
04FEB2012    2012     6
05FEB2012    2012     7
01JAN2013     2013    1
12JAN2013    2013     2
08MAR2014   2014    10
09MAR2014    2014    11
If it is the first instance of the year and has a value of 2 than it should be reduced by 1. Here is the output that I need
FiscalDate   year   Value
01JAN2012  2012    1
14JAN2012   2012   2
15JAN2012   2012   3
04FEB2012    2012   5
05FEB2012    2012    6
01JAN2013     2013    1
12JAN2013     2013    2
08MAR2014    2014   10
09MAR2014     2014   11

Data is sorted by date

[Astounding]

As long as YEAR is also part of the data set, you can use it:

data want;

set have;

by year;

if first.year then do;

   if value=2 then increment = -1;

   else increment = 0;

end;

retain increment;

value = value + increment;

run;