@REM E M B E R   Y e s t e r d a y
@REM 2008, Chaoji Li<lichaoji@gmail.com>
@echo off
REM You may need to adjust the following three fields according
REM to the date format in your system.
set _y=%DATE:~6,4%
set _m=%DATE:~0,2%
set _d=%DATE:~3,2%
set _date=%_y%%_m%%_d%
set /a y= %_date% - 1
set _d=%y:~6,2%
set /a _leap=%y%-%y%/4*4
set _feb=0229
if not %_leap%==0 set _feb=0228
if not %_d%==00 goto DONE
if %_m%==12 set y=%_y%1130& goto DONE
if %_m%==11 set y=%_y%1031& goto DONE
if %_m%==10 set y=%_y%0930& goto DONE
if %_m%==09 set y=%_y%0831& goto DONE
if %_m%==08 set y=%_y%0731& goto DONE
if %_m%==07 set y=%_y%0630& goto DONE
if %_m%==06 set y=%_y%0531& goto DONE
if %_m%==05 set y=%_y%0430& goto DONE
if %_m%==04 set y=%_y%0331& goto DONE
if %_m%==03 set y=%_y%%_feb%& goto DONE
if %_m%==02 set y=%_y%0131& goto DONE
if %_m%==01 set /a y=%_y% - 1 & set y=%y%1231& goto DONE
:DONE
set YESTERDAY=%y%
echo %YESTERDAY%