Dr. Monzer Kahf, a prominent economist and counselor says:

“…people differ in their life style and each one is entitled to the way she/he feels okay with. Your past life style was such that you ended up saving a sum of money. Once this sum reaches (or have reached) the equivalent of Nisab (# Euro 1000) and you find that after a lunar year (354 days) from that day you also have at least a Nisab, you are then required to pay Zakah on all that amount at the rate of 2/5% and you should repeat paying every lunar year as long as you have the amount of Nisab at least. Having this amount while your expenses are taken care of (regardless of your life style and having one year passes and you also have the same at least means, you are rich! Who else is a rich person/family if not one who has all needs of life paid for and yet has some good amount extra and has such extra amount even after a year passes?! Remember that you are richer than 98% of all humanity!”