Determining middle class using purchasing power parity will have different results from country to country and from conditions to conditions (ie, economic crisis). I personally think, that despite all definitions, middle class is when a family, as a whole, can save a portion of their income after all their normal expenditures (basic + minimum requirements ie. going to movies, eating out) being deducted. As long as a family can not save for their future expenditure, they are not middle class. They are still considered lower class despite their earning is more than USD2 per person per day. When saving is practised by a family, then they can be considered middle class, which by default shows some kind of governance in the family. This is a micro governance shown by a middle class. Translate this into community, we will have an accumulated savings and collective governance.