President Donald Trump's boast the economy is the best it has ever been is only true if you are rich, according to multi-billionaire businessman and former New York Mayor Mike Bloomberg.

In an opinion piece for MarketWatch posted Thursday, the Democratic presidential candidate taunts Trump, writing "President Trump pushed through the biggest tax cut for the wealthy in history, and nearly all the money goes to people like me, who don't need it."

"Sure, the stock market is at an all-time high," he wrote. "But almost half the country doesn't own any stocks. And, yes, the unemployment rate is low. But nearly half of all workers are in jobs that earn $18,000 at the median.

"In fact, the share of national income going to workers — rather than investors — is near an all-time low."

According to Bloomberg, "too much wealth is in too few hands."

"As a candidate, Trump promised to take on these issues," he wrote. "As president, he has been in the pockets of the special interests that dominate Washington."

He pointed to Trump's promises to keep open a Lordstown, Ohio, GM factory – that later shut down – to help farmers, only to wage trade war that cost them "billions of dollars."

"[W]e faced serious economic problems before President Trump took office. That's one of the reasons he won. He promised to fix them," he wrote. "Instead, he has made them worse."

Bloomberg said if elected he will concentrate on "preparing people for good jobs."

"Creating good jobs is not something I just talk about," he wrote. "It's what I've spent my whole career doing. That's a key part of the message we need to beat Trump. I'm ready to take it directly to him."

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