I have a portion of a database that keeps track of wait time. I have a report that is supposed to group my data by start time, and average the number of minutes waited for each hour. I have a summary field for number of minutes waited. I get the report all laid out and it's working great. Then, suddenly, it stops grouping the data on the preview view. I can still see the grand total, but not the sub-summaries. I have no idea what could be causing the sudden change. The only way I've found to fix it is to recreate the report from scratch.
