How much is invested each year to keep the panama canal going?

Almost 2.6 billion U.S. dollars was the toll revenue generated by the Panama Canal during the fiscal year 2019 (from October 2018 to September 2019), up from around 2.5 billion U.S. dollars reported a year earlier. Around 46.2 percent of that revenue was generated by tolls from container vessels

the answer is "by providing data about careers and annual mean wages"