Whether government, corporation or consumer, credit became the main way to survive 2020, as indicated by spiking debt levels across the entire global economy that, in some cases, surpassed even World War II levels.

Bloomberg reported that global debt increased by $19.5 trillion in 2020; this borrowing served as a sort of bridge to survive the year in the wake of the pandemic's economic chaos. Yet while total debt has now risen to 140 percent of combined gross domestic product (GDP) of the top seven economies, up from 85 percent in 2005, servicing this debt has never been easier due to central banks slashing interest rates to record lows and buying assets at record highs. This means that debt costs have actually shrunk from 2 percent of GDP to 1.5 percent.

Corporate bond sales also reached historic highs last year, a 28 percent jump representing $4.4 trillion of new borrowing, something the central banks made possible with their aforementioned asset purchases: with these entities pledging to buy as much corporate debt as necessary to stabilize the economy, corporations don't have to worry as much about who will buy their debt if they issue bonds because they know, if all else fails, the central bank will.

The debt binge isn't only on the macro level: CNBC reports that consumers relied on their credit cards more last year as well. About half of all Americans with credit card debt, roughly 51 million, said their credit card balances were higher than the year before, and 44 percent said this was specifically because of the pandemic. At the same time, the average credit card balance went down from $6,194 to $5,315, which CNBC suggested was due to the K-shaped pandemic recovery.

Bloomberg noted that this current debt binge (which is really an acceleration of the overall rising levels of debt that had been brewing for years) is sustainable only so long as debt remains relatively cheap. If, for example, interest rates increased by just 2 percent, then the cost of servicing U.S. sovereign debt would rise from 2 percent of GDP to 6 percent by 2030, equal to all outlays for Social Security. However, for now, this looks unlikely to happen, at least in the United States, as the Federal Reserve recently indicated that interest rates will remain ultra-low for the foreseeable future.