Hiya bertie, thanks again for helping me. I can't get this to work. I opened the VB and inserted a module into several sheets and added the code, but nothing happens.

Here's what I'm doing:

Each worksheet records the performance data of 10 machine operators for a day. They use a time clock to record the time it takes them to complete various tasks. They use a worksheet to record the data; there are several mathematical operations the operators must perform on the worksheet, the most challenging being the addition and subtraction of time. The worksheet is then given to the data entry person who then records the data in the workbook. The data entry person just records the days totals as calculated by the operators, has no time to check the 20 or so calculations if there's an error.

The operators are listed in A2:A11.

The Column headers are:

Col B = Available time, typically 630 minutes

Col C = Set up time, how much time is spent preparing a job

Col D = Print time, how much time it takes to finish the project

Col E = downtime, time lost due to circumstances beyond the control of the operator.

Col F =sum(B2-E2), the actual time available to the operator to perform all the tasks required in the day.

Col G =sum(C2+D2)/F2, this shows how efficient they were in the use of their time, the goal is 85%, and this is where the errors in their calculations become evident, they get greater than 100%.

There are another 8 or so columns of unrelated information and so in column P I have this formula: =IF(G2>100%,"1","") which I hope will trigger the sheet tab color change.

Could the formula in each cell of Col P be interfering with the macro?

Hey I hope this is as much fun for you as it is for me

thanks again, Kendel