The short-term direction of stocks hinges on Wednesday’s inflation report, and JPMorgan broke down how the market will react to different numbers.

The Bureau of Labor Statistics is set to release its closely watched reading on the December consumer price index at 8:30 a.m. ET. That’s expected to show 0.3% monthly gains on both the headline and core readings — the latter excluding food and energy — and respective annual inflation rates of 2.9% and 3.3%, according to a Dow Jones survey of economists.

JPMorgan’s trading desk focused on the monthly core CPI number as the most critical, and dissected how the S&P 500 might move depending on the reading.

The largest bank in the country said the base case scenario is that core CPI comes in anywhere between 0.17% and 0.23%, which could result in a knee-jerk rally in the S&P 500 in the range of between 0.25% and 1%

If the inflation reading is much cooler than expected, in the range of a 0.10% to 0.17% increase, the S&P 500 might climb 1% to 1.5%.

“This dovish outcome is likely achieved via a combination of cooler home inflation and an increase in the deflationary impulse from Core Goods,” the Wall Street firm said.

If December core CPI is between 0.23% and 0.30%, it could lead to a 0.75% to 1.25% loss in the S&P 500.

“This hawkish outcome likely comes to fruition if Core Goods deflation flips to being inflationary and/or [there’s a] loss of disinflation momentum from housing,” JPMorgan said.

The crucial inflation reading could influence the Federal Reserve’s interest rate policy this winter. While market pricing overwhelmingly points to the central bank holding its benchmark lending rate steady at 4.25% to 4.50% at this month’s Fed meeting, Chairman Jerome Powell could still could lay the groundwork at his press conference afterward for where rates might move later in the year.