Timer function needs improvement

[Mike K]

Oh wise ones,

I use the following function to indicate the time a cell "D2" is less than
350. I have a macro that refreshes (recalculates) D2 every 2 seconds. It
works, but is not very accurate. How can I convert this function, maybe vba,
to keep track in real time how long D2 is less than 350? I'm guessing the
overhead to calculate and update a cell takes a wee bit longer than 2 seconds.

I6 contains =IF(D2<350,I6+2,0)
J6 contains =I6/60
K6 contains =INT(J6) 'minutes
L6 contains =(J6-K6)*60 'seconds

Thanks,
Mike