LONDON (Reuters) - Donald Trump has so far sent comparatively fewer market-moving social media posts since being re-elected than during his first term in power, a study by U.S. investment bank JPMorgan has estimated.

The bank's analysts found that only 10% of the 126 posts Trump had published this time around on sensitive topics such as trade tariffs, foreign relations and economics had caused clear currency market moves.

The numbers are picking up though. Last week he sent more than 20 posts linked to those issues, double January's average. That, however, is still well below the 60-a-week he peaked at during his 2018-19 trade rows with Mexico and others.

"Among the different topics, the posts on tariffs have been the biggest market movers," JPMorgan's note published on Monday said, adding that closer to a third of those ones had been market moving.

The largest impact so far has been the more than 2% and 1% falls in Mexico's peso and Canada's dollar, respectively, seen at the start of February when Trump posted he had used emergency powers to implement 25% tariffs on Mexico and Canada - a move he postponed two days later.

Others focused on China meanwhile have caused moves in both directions depending on their tone.

The yuan dipped after Trump threatened tariffs over Fentanyl supply shortly after his re-election. But the currency also rose in mid-January after the U.S. president said he had "a very good" phone call with China's President XI Jingping.

JPMorgan's analysts said their backtesting showed that trading on Trump's posts wouldn't have been very profitable either so far.

Buying the dollar versus a basket of G10 high beta currencies, or the most directly-impacted individual currency for between five and 180 minutes after each post would have been "disappointing" they said, estimating no more than a 4% gain even under "highly optimistic" assumptions.

While Trump is sending fewer market moving social media messages at this stage, he has stepped up direct communications from the Oval Office with almost-daily question and answer sessions with journalists.