The thing is, You HAVEN'T been better historically. You have gone through relatively short stretches of being better, you have also going through relatively short stretches of being worse.
Historically, both this year, and in the past few years, you're right about on historical average. Yes, if you specifically choose 4 years, you're slightly below averge, but if you choose 3 years, or 5 years, you're not.
I don't know you, but it strikes me that you choose 4 years so you can get both bad years, but not include one of the good years, and that's dishonest, and should be beneath you.