Hi Thuy... I'm not very comfortable with using "the figure for..." to mean " the number for". I can understand it but "figure" doesn't feel like the best word to use if you are trying to indicate a number in a table or a graph. I would be more inclined to use the words "statistic", "amount", "quantity", etc.
That said, I don't think it would be horribly wrong to use "the figure for France has increased over a period of ten years". Alternatively, you could also say "the figures for France have increased over a period of ten years".
Hope that helps.