The IRS has only 650 employees born in 1990 or later out of a total work force of 87,000. The agency is struggling after five straight years of budget cuts. It faces a long-term problem as a hiring freeze prevents it from replacing workers who leave . . . . US corporations now have $2.1 trillion in earnings parked in offshore holding companies, Bloomberg News reported after surveying US securities filings of 304 US multinational corporations. The earnings will become subject to US income taxes if repatriated to the United States.