Is there any way to speed up this macro.. COUNTIF

Hi, I'm using a macro for COUNTIF function, for couple of rows its ok but my data contains more than 800k rows so calculation is very slow. Is there any vay to speed up this macro or can you suggest another macro. (please see attachment)

ps: i tried screenupdate:false but it did not worked..

thanks..

SAMPLE_COUNT.xls

application.calculation = xlcalculationmanual

Remember to put it back to application.calculation = xlcalculationautomatic at the end

thanks krishns, i tried this too, it did not work. this method only disable auto calculation. my problem is, when you run macro the proccess takes too long..