-- write a SQL query to find the average player salary by year.
--     Sort by year in descending order.
--     Round the salary to two decimal places and call the column “average salary”.
--     Your query should return a table with two columns, one for year and one for average salary.
SELECT "year", ROUND(AVG("salary"), 2) AS "average salary"
FROM "salaries"
GROUP BY "year"
ORDER BY "year" DESC;