Big tech is getting bigger.

Apple, Alphabet, Microsoft, Amazon and Facebook, the world’s five most valuable public companies, added $181 billion to their combined market value on Friday.

Investors piled into the group a day after Alphabet, Microsoft and Amazon reported better-than-expected earnings.

For the stock market, it was more of the same. Those five companies have gained almost $900 billion in market capitalization over the past year. They’ve each outperformed the S&P 500 in 2017, and have been the top contributors to the index’s 15 percent gain.

Despite potential political and regulatory pressures on Google, Facebook and Amazon and loud voices of concern about the tech giants hurting competition and controlling too much of our data, the stock moves reflect financial performance. And the performance is staggering.

People are clicking on more Google ads. Amazon, which picked up $62 billion in stock market value on Friday, is delivering more of everything. Those two companies plus Microsoft are picking up share of the rapidly growing cloud-computing market.

Even though Facebook and Apple don’t report results until next week, investors drove the stocks up on Friday to the tune of a combined $51.4 billion. Facebook is projected to record 40 percent sales growth on Wednesday. The next day, Apple is expected to report growth of more than 8 percent, thanks to sales of 46 million iPhones, according to FactSet.

The tech leaders pushed the S&P 500 and Nasdaq to record closes on Friday. Rallies don’t last forever, but investors aren’t finding many reasons to bet against tech.