President Trump signs an executive order as chief of staff Reince Priebus looks on in the Oval Office of the White House on Jan. 23. (Saul Loeb/AFP/Getty Images)

Since his inauguration, Donald Trump’s net approval rating — already at a historic low for an incoming president — has taken a further hit. According to the Pollster average, about 50 percent of Americans disapprove of the job Trump is doing as president while 43 percent approve, for a net approval rating of -7. In Gallup’s polling, Trump’s net approval is -10.

So what next? At the end of Trump’s first 100 days, where will his approval rating be? As part of our First 100 Days forecasting tournament, conducted in partnership with Good Judgment, forecasters were asked this question: “What will Gallup report President Trump’s net approval rating to be on 28 April 2017?”

Forecasters can choose from three options: below -15, between -15 and +15, or above +15. For comparison, President Barack Obama was at +22 in Gallup’s last poll. Here is a graph of the forecast:

Forecasters believe the “middle” outcome is most likely, giving Trump a 72 percent chance of having a net approval rating between -15 and +15. They believe Trump has very little chance (6 percent) of attaining a more positive rating than +15. In fact, the forecasters give Trump about a 1-in-5 chance (22 percent) of ending his first 100 days in office with a net approval rating below -15.

It is interesting too that there have not been sharp swings in the forecast, despite the dramatic events and controversies of Trump’s first weeks in office. This may imply that the drop in Trump’s net approval rating does not necessarily portend a larger drop (below -15), although that scenario isn’t impossible, either.

Of course, the range between -15 and +15 is not small. A net approval rating of -10 has quite different political implications than +10. And this forecast does not provide a clear sense of where Trump’s current net approval rating is headed next. But the chances that it will fall significantly appear larger than the chances that it will rise significantly.

Small wonder, then, that Trump and his staff are already rethinking their tactics.