For markets, this is another sign that concerted tightening by global central banks is progressing.

Historically, peaks in the U.S. rate cycle combined with rising equity volatility and a moderation in earnings momentum all signal U.S. equity performance.

The caveat is liquidity and M&A activity, which is continuing to provide very strong support for the market.

The move is significant in the sense that it signals the authorities in China are now acting to reduce rates of economic growth, despite low levels of inflation.

Markets are slightly vulnerable in terms of current positions. Equity markets have clearly run relatively far in relatively short order.