[jyl]

Watch to see if negative core CPI is a trend.

Also watch PPI versus CPI, if the latter is below the former, that is negative for corporate profits.

Negative inflation (deflation), if it is sustained, is negative for the economy. Also for the stock market, I posted on that in 2008 I think.
Note that liquidity (in the sense of money supply) has been contracting. Contrary to what the hyperinflation bears say.

Basically, you don't want to see negative core CPI. It is bearish.