iPhone: How copy text to pasteboard in order to paste into Numbers cells?

Question

I'm trying to copy some tabular data from my app and paste it into a Numbers spreadsheet. The data being copied to the pasteboard is tab-delimited. For example:

UIPasteboard *pasteboard = [UIPasteboard generalPasteboard];
pasteboard.string = [NSString stringWithFormat:@"%f\t%f", 1.1, 2.2];

I am expecting it to paste across the Numbers spreadsheet cells, however it pastes it all into one single cell. If I copy multiple cells from Numbers, I can paste it as tab-delimited in other apps (e.g., Notes). So presumably there is some way to copy it to the pasteboard to indicate that data is delimited. Any ideas how to get this to work? Thanks.