FIrst thing is to reverse your columns, so that speed in in column A. As you
point out you can get the max speed with the MAX() function. Then you can
use VLOOKUP() to find the associated time. If speed is now in A1:A100 and
time is now in B1:B100 then use:

=VLOOKUP(MAX(A1:A100),A1:B100,2)
--
Gary's Student


"TECHNOID" wrote:

Suppose I have two columns of data. Column A is the independent variable,
say TIME. Column B is the dependent variable, say SPEED. The data are
collected on a car that starts from rest, accelerates, decellerates, then
stops. Clearly, the car attained some maximum speed during the test. I can
find the value of the maximum speed by using the worksheet function =MAX(B),
but I want to know at what time (column A) the maximum occurred. Of course I
can do a manual (visual) search, but this is laborious and eye-straining for
reams of data. What single worksheet function (or more likely, nested
functions) can I use to return the time value?