The "misery index" that has been used to predict election winners since 1980 is showing positive signs for Harris, but it's a close call.

• The misery index, which has accurately predicted presidential elections for four decades, suggests that Kamala Harris could win if trends continue.
• The gauge combines the unemployment rate and annualized inflation rate to provide insight into the level of voter dissatisfaction with the economy.

The economic misery index, which accurately predicts elections, is leaning towards a Kamala Harris win, but it's tightening up as the race nears its end.

The "misery index," which is the sum of the unemployment rate and the annualized inflation rate in the U.S., has accurately predicted 15 out of the past 16 presidential races, including all contests since 1980, according to a study by research firm Strategas.

The jobless rate for August decreased to 4.2%, but this did not raise the index above the level that Strategas found would lead to the incumbent party losing the election.

According to Strategas, the Democrats need a misery index below 7.353 in October to maintain power, as determined through exclusive analysis of historical trends.

If voters are not unhappy enough with the economy to vote out the incumbent party, it suggests that the economy is not in a bad enough state.

Daniel Clifton, Strategas' head of policy research, stated in a Monday note to clients that while the unemployment rate is still a concern, falling gasoline prices are helping to keep economic woes contained enough to aid Democrats in the upcoming election. Despite this, Clifton believes the race is still extremely close.

The debate between Harris and Republican Donald Trump, hosted by ABC News in Philadelphia, will take place on Tuesday night at 9 p.m. ET, with Clifton's commentary preceding the event.

The stakes in this debate are as high as they have ever been due to the tightness of the race, he stated.

The consumer price index for August will be released on Wednesday at 8:30 a.m. ET, and economists predict it will increase by 2.6% compared to the previous year.

The Federal Reserve's goal of 2% yearly price growth would be reflected in a decline from the 2.9% year-over-year rate recorded in July, as well as a broader downtrend in annual inflation from the runaway levels seen early in the Covid pandemic.

The misery index has decreased significantly in recent years due to a decrease in annualized inflation. Notably, the misery reading was above the 7.353 threshold just last year.

If the labor market's cooling concerns lead to an increase in unemployment, Harris may face challenges. Although August's jobless rate decreased slightly, payrolls expanded less than expected in August, causing market participants to be concerned.