Minor quibble - I checked for Philippines as I'm from UK and go there quite a lot. The DB says the visa exemption is 21 days - it's actually 30 days.
Where do you get your data from? Trawling embassy sites? That's quite a lot of work as the information does change. Take Thailand for example - they have made so many changes over the years it's hard to keep up with - even the border staff often don't know what the latest regulation is! :)