The top five U.S. tech companies have taken a huge hit during this recent sell-off.

The combined market value of Apple, Alphabet, Microsoft, Amazon and Facebook is down $437 billion, as measured by the decline from each of the stocks’ respective 52-week highs — all of which occurred on or after Jan.18 of this year — from closing to closing, according to FactSet.

Alphabet has seen its shares and market value fall the hardest among the five, but recent heavy selling has meant plenty of pain to go around for large-cap tech investors.

Alphabet’s disappointing fiscal fourth-quarter results last week started the wave of selling in that stock last Friday, the same day the market turmoil began.

Yet Amazon and Facebook, which both initially rose last week after better-than expected quarterly earnings, have also been hit, along with Apple and Microsoft.

Here’s how much the five most-valuable technology companies have fallen from 52-week highs, and what they lost in market value:

• Apple: down $123.7 billion in market cap
• Alphabet, down $124.7 billion
• Microsoft, down $77.4 billion
• Amazon, down $48.4 billion
• Facebook, down $62.6 billion
• Total, down $437 billion