"First of all I should say that I agree with davy" - Norman Tebbit.

You aren't poor, you've just chosen to adjust the overall pattern of your income on the expectation that temporarily it'll be low and in future it will be high. Just because for a relatively short part of your working life you aren't earning a decent salary doesn't make you poor. Similarly, living in a decent central London flat, with tons of amenities in the area, surrounded by the only decent public transport network in the UK, and buying your food from Borough Market (I am basing all my analysis on parties you've held!) does not make you poor. But if you lived in a cramped, damp council flat in Nitshill on the edge of Glasgow, reliant on a few random clapped-out buses and only able to afford to eat out of the local Lidl, with no education and no chance of a decent job, then you'd be poor. Finally, any generic social metric is by definition going to be partially inaccurate, so the question is whether it is suitable when taken across society as a whole - not whether it is perfect in 100% of cases because you'll never be able to define such a thing - trying to do that would be a job for life!