In early 90, that was thirty years ago, my aunt and my uncle of mother side came from Mainland to visit us. As younger generation to them, my elder brother and I chipped in $4,000 as "greeting present" and gave each of them $2,000. (then less than a months salary of mine) I will never forget the complexion my aunt evinced on the spot: a mixture of surprise, appreciation, and a little embarrassment. In those days, $2,000 approximately valued over RMB10,000, that was a big fortune for ordinary people or a family in China Mainland.
But when my aunt showed her ID card to us, suddenly I realized the gap of wealth between Taiwan and China Mainland would be erased soon or later. That is a well laminated plastic card with perfect hue and shape, having some function of data processing. Do you know what kind of ID card we were using then? A paper one of handwritings and pasted photo.
The following video may tell you why the "national" wealth of Taiwan dropped from 45% of the the GDP of China Mainland in early 90 to 1/22 by now.