They do change depending on what river or lake. There are lots of charts out there if you Google the area you are fishing in. The charts do not accommodate for yearly weather changes like drought. Our hatch numbers have been down as insect numbers decline, some where major hatches are much smaller. I like to keep notes in my fishing diaries about hatches and the bugs I scoop streamside to record for future years. Watch the water and pick up a good book on insects for ID. Another great book if you are really into it is The Phenological Fly By Bob Scammell. It matches insect super-hatches of the West with the blooming of native streamside wildflowers, shrubs, and trees.
North Ram river
Chart
Bow River
Chart
Another
Chart