Great Cruiseline offers nightly dinner cruises departing from several cities on the East Coast of the United States including Charleston, Baltimore, and Alexandria. Dinner cruise tickets sell for $$50$ per passenger. Great Cruiseline's variable cost of providing the dinner is $$20$ per passenger, and the fixed cost of operating the vessels $($depreciation$,$ salaries, docking fees, and other expenses$)$ is $$210,000$ per month. The company's relevant range extends to $12,000$ monthly passengers.

If Great Cruiseline sells an additional $500$ tickets, by what amount will its operating income increase $($or operating loss decrease$)?$