The Japanese stock-market index that fell by more than half from its 1989 peak during Japan's asset-price crash was the Nikkei 225.
The Nikkei 225 reached an intraday record of 38,957.44 on December 29, 1989. Japan's enormous rise in share and land prices then reversed. By the early 1990s, the index had lost well over half its value, while banks and companies struggled with bad loans and falling collateral values.
The boom was supported by easy credit, strong corporate investment, and speculative property and equity purchases. When the Bank of Japan tightened policy and the bubble deflated, the consequences extended far beyond the exchange. Weak banks, reduced investment, and prolonged deflation contributed to the period later called Japan's “Lost Decades.”
The Nikkei and TOPIX are often confused. The Nikkei 225 is a price-weighted index of 225 leading companies, whereas TOPIX is a broader, capitalization-weighted measure of companies listed on the Tokyo Stock Exchange's Prime Market.