Oh, how you will be hated by many devs here ;-)
They struggle and toil and have no idea why their sales do not increase, yet you wonder why your's increased.
If you find out, you could kindly give hints and tipps to those aspiring devs. But yeah, what no time said. If you know where the traffic comes from, you can have an educated guess.
But the algorith is known to mix things up now and then.