US stock uncertainty is shrinking to a degree not seen since the day after President Donald Trump's election victory.

Thank France.

On the heels of the first round of the French election, the CBOE Volatility Index, or VIX, plunged 19% as of 10 a.m. ET, on pace for its biggest daily drop since November 9. The index, which is a measure of expected price swings in US equities that serves as a barometer for investor nervousness, generally falls as stocks rise.

As such, the selling of VIX contracts usually translates to a bullish wager on the S&P 500. The benchmark rose 1.1% on Monday, headed for its biggest increase since the start of March, amid gains in other global equity indexes.

Investors were apprehensive heading into France's weekend vote. Now that the path looks clearer for centrist candidate and market favorite Emmanuel Macron to seize victory next month, they're feeling relieved.

Monday's drop in the VIX brings the gauge down to 11.89. Even before the decline, the index was looking subdued, trading well below its bull market average of 18.78. It was locked in the range between 10 and 14 for the first three months of 2017, and now sits there again.

Still, hedge funds and other large speculators aren't taking any chances. As of April 11, they were the most bullish on the VIX since the start of December, according to data from the US Commodity Futures Association. While those investors pared those bets slightly last week, their bullishness still remains above the one-year average.