Dividends and Buybacks Now Larger Than Total Earnings for the Entire S&P 500

How much of the buybacks+dividends were companies returning extra cash they have accumulated to the shareholders?

I mean, some companies like Apple are doing the right thing by doing buybacks. Top 20 largest buybacks in Q4 2018 made 44.42% of the SP400 buybacks and they seem to have good net financial position.

Only indebted companies taking loans for buybacks+dividends is troubling.