Hillary Clinton is going to expand on her economic agenda this week with a proposal to slap higher capital-gains tax rates on short-term investors with the goal of encouraging long-term growth.

The plan is supposed to address what some consider overly short-term thinking by corporations. Capital-gains taxes would be updated with a sliding scale of three new rates that vary depending on how long the investment is being held, according to the Wall Street Journal.

Investments held less than a year would be taxed at regular income rates, as high as 39.6 percent, whereas investments held for two to three years would only be taxed at a maximum of 23.8 percent for top-grossing investors.

The top capital-gains tax rate was cut to 20 percent under Bill Clinton's administration, right before the Internet boom of the 1990s.

While Democratic rival Bernie Sanders focuses on income inequality and Martin O'Malley hammers Wall Street, Clinton will say she is trying to encourage long-term growth. She hopes her message of curtailing short-term investments will provide long-term economic security.

Republicans were quick to criticize the proposal. "While Republicans focus on growing the economy and Americans' paychecks, Hillary Clinton is proposing to grow Washington and the IRS by raising taxes," said RNC spokesman Michael Short. "The contrast couldn't be more stark."

During the address, Clinton also plans to speak about executive compensation as well as the risks and benefits of shareholder activism. The campaign has yet to finalize the details of where and when the speech will occur.