Hong Kong’s economy contracted 6.1% in 2020, its worst performance since 1998 during the Asian financial crisis. But stock market gains provided some reprieve; the benchmark Hang Seng index was up 5% since fortunes were last measured 13 months ago. That resilience helped boost the combined net worth of the 50 richest by 7.5% to $331 billion, up from $308 billion last year.