Financial industry is too wide, what part are you talking about, brokerage, hedge funds, private equity, money managers, retail banking, corporate banking, insurers?
If you are talking about money managers, the bulk of the money is in fees. Market gain doesn't usually bring much directly but obviously it increases the pot and may brings fresh money both of which bring more fees.
For hedge funds and private equity, the reverse is usually true.
Great article, that has been my feeling all along.