"Trade wars are good, and easy to win," US President Donald Trump tweeted in March 2018. "When we are down $100 billion with a certain country and they get cute, don't trade anymore - we win big. It's easy!"

But a new report says Americans aren't winning.

Since Trump made that comment and started imposing tariffs, the price tag of duties for American businesses and consumers has added up to nearly $22 billion, according to a report issued on June 21 by "Tariffs Hurt the Heartland", a national campaign against tariffs supported by more than 150 US trade groups representing agriculture, manufacturing, retail and tech industries.

The report's data, which is broken down by individual tariff action, shows that of the $22 billion, $15 billion came from tariffs just on Chinese imports. The data runs through April 2019, the most recent month available from the US Census Bureau.

That $22 billion was before the US administration more than doubled the tariff rate on $200 billion worth of Chinese products in May, so current totals are likely much higher.

In addition to the $15 billion from tariffs on China, $4.6 billion has come from steel tariffs, $1.3 billion from aluminum tariffs and $460 million from tariffs on solar products and washing machines, according to the report.

Iowa Republican Senator Charles Grassley, who is leading efforts to produce legislation that would take back power over tariffs from the presidency, has given the same estimate.

US Customs and Border Protection has assessed more than $15.2 billion in tariffs on China and more than $6.5 billion from those levied on steel and aluminum import.

"To be clear, American importers and consumers are paying for these tariffs," Grassley said at a Senate Finance Committee hearing on June 18. " $22 billion out of the pockets of hardworking Americans is not in our national best interest."

"Congress is at fault any time a president exceeds, uses legislative power to do certain things," Grassley said on June 12. "It's got nothing to do with Trump except Trump's use with tariffs."

The data also shows exports generally decreased by 2.5 percent from April 2018 levels.

The US Department of Agriculture expects farm exports to fall by nearly $2 billion to $141.5 billion in fiscal 2019, largely because of tariffs China levied last year to hit back against the US administration.