Hi! I think what you are seeing is that the data for the chart has several numbers for each yearMonth (one number for each serviceMain value). In the second chart, filtered for a single serviceMain value, it’s one number per yearMonth, so everything look correct. In the first chart, there are several numbers, and Grist looks like it’s picking one value to plot – probably the value for the first serviceMain it encounters (but I am not sure).
This has been an issue with charts, which we haven’t found a good way to deal with. The best suggestion I have is to select the “Split Series” option, select serviceMain in the Split Series dropdown, and probably also select the “Stack Series” option.
Then all the different serviceMain values would be stacked in each bar, so the total bar should become correct.