Develop a sub total id or simulate colspan with css

[carlos-granadeno]

First of all, congratulations for this great data grid. I only want to suggest if you think in include a subtotal line with some id "sub" or something like that and with a CSS that simulate a colspan putting "subtotal" as label.
Right now i do it manually, using a historic_variable to check in the FOR the change of some topic, to summarize or count some columns, then if country <> country_old ,, i sent the totals to the grid... but this php's.
Just an idea...
good job again.