Just ahead of Tax Day, California senator Kamala Harris released fifteen years of her tax returns in her bid for the Democratic nomination for the 2020 presidential election.

Harris' full disclosure is a "stark contrast" to Trump, her campaign said. The California senator also supports a proposed federal law that would require a president's tax returns be made public.

Harris' taxes were relatively straightforward in her early years of elected office. Her income as district attorney climbed from around $142,000 to just over $260,000 during her two terms in office; her average effective tax rate at the time was around 20%.

Her income dipped to about $160,000 when she took office as state attorney general in 2011, and fell further the next two years. Harris made no charitable contributions her first three years in that job.

After her marriage to Emhoff in 2014, Harris' fortunes grew substantially. That year, the couple reported more than $1.3 million in income and paid more than $410,000 in taxes. They reported giving more than $60,000 to charity, including $15,000 to the American Cancer Society.

Those donations dropped in subsequent years, ranging from around $18,000 to $37,000. The bulk of the giving was through Emhoff's law firms; other favorite causes include UNICEF and Harris and Emhoff's respective alma maters, Howard University and the University of Southern California.

Emhoff, a litigator specializing in intellectual property, was a partner at the firm Venable before he joined DLA Piper last year. The returns show Emhoff earning at least $1 million each year for his work.

In the five years the couple have filed joint returns, they have paid more than $2 million in taxes, with an average effective tax rate of more than 30%.

Now it's time for Donald Trump to pony up his tax returns. To help nudge him towards transparency, the state of Illinois has passed legislation mandating the tax returns from any candidate who wishes to appear on their ballot, joining the state of Washington and sixteen other states currently debating similar legislation.