Relation between income and happiness

My annual income is about ￥4.7〜4.8 million.

That of my friends who were same class in my high school or college is probably 1.5〜2 times as high as mine.

Although my income is lower than them,I am still happy.

Because I earn money which I feel is enough.

I think that happiness isn't almost in promotion to a income beyond some extent.

But when I think of marriage and child raising,I feel anxiety.