The sort order for data in Reports was changed in TAC Vista version 5.1.7.
The newest data should be in the bottom in TAC Vista 5.17the newest is in the top.
This is when the inserting a trend log to a report and the period "Number of values" is chosen, "start/stop time" and "Period" works like it did in previous versions.
TAC Vista 5.1.7
This is an error and have been fixed in hotfix 41 for TAC Vista 5.1.7.
And the sort order is correct in TAC Vista 5.1.8 and later versions.
Install hotfix 41 for TAC Vista 5.1.7.