Thank you Paul, I found some inconsistent data in the grm_time field of the data source and that seems to have cleared up that problem.

But this doesn't explain why the 'starts', 'end' and 'e1_start', 'e1_end', 'e2_start' and 'e2_end' fields still merge as decimals only. With reference to my datasource in post 25, all these columns are numeric data formatted as time. No data inconsistencies (that I have easily spotted). In the e2_start and e2_end fields there are blanks. Would this contribute? I don't know how to overcome that concern because there would be no time applicable in those cases. I wouldn't be able to use 0.

When you use my datasource from post #25, with your report, would you not get the same results as me if the data was inconsistent? You said all the times formatted OK for you ... but we're using the same datasource and getting different results with the same report.