Below is an updated look at S&P 500 sector weightings. As shown, Technology now makes up more than a quarter of the pie, while Financials, Health Care, and Consumer Discretionary are the next largest sectors (in that order).
Notably, the Consumer Discretionary sector's weighting of 13.03% is nearly twice as large as the weighting of 6.61% for Consumer Staples. Below is a chart showing the spread between the weighting of the Discretionary sector versus the Staples sector. At +6.42 percentage points, the spread is at a record high going back to 1990.
The record spread between Discretionary and Staples certainly tells us that the economy has been rolling, but it should also start to offer a bit of a warning sign for investors. The prior record for this spread came at the very end of the dotcom boom of the late '90s, when Tech was on fire (as it is now) and the economy was also rolling. The low for the spread came at the depths of the Financial Crisis in early 2009. It's not rocket science - you know which of these two points in time was the better buying opportunity for investors!