Sure. Just take monthly and quarterly averages. Eventually you'll have averages for several years and you'll be able to track strong months and quarters. With me it helped with marketing. I realized in April that my suburban business picked up, so I could do targeted marketing late March in the areas that I visited more. All of my marketing goes to blocks or regions of a city. If I've never marketed outside of a region that has similar clients and sizes I can estimate that moving into that section of the city will earn me x number of clients.

I can then market on that area and compare my projections with what happened and try to figure out why. After a year you can compare months to themselves and see real data of how each marketing campaign affected each quarter.

I brake each month quarter and year up into basic accounting tables.

Income is broken into from repeat clients and new clients. Then to what I did for them, hand that's not easy to break down on reddit but imagine sometimes I just do a living room, sometimes I do all of the throw rugs, etc.) Then further broken into how they heard about me. Word of mouth? Just saw my truck? Google?

I don't know how it will affect your business but for me. Paying for Google ads at the right time of year shows exponential roi.

Then expenses, marketing, vehicle upkeep (insurance, oil changes, etc), payroll (always my biggest hit, even when I'm doing jobs), inventory.

With these numbers you can figure out the margins pretty easily. However, someone who went to college for this stuff could probably give you a better system.