Charlie Cook and his team at The Cook Political Report are out with eye-popping new data that help show why Congress is frozen — and why happy talk about working together to do big things, whether by optimistic centrists or by people in power who need to put points on the board, is belied by data.

Key trends — all 20 years in the making, but hardened and in some cases accelerated by the "hyper-polarized" election of 2016 — from the 20th anniversary "Cook Political Report Partisan Voter Index," by David Wasserman and Ally Flinn:

• The decline of crossover districts: Only 35 of the nation's 435 House districts went for presidential and House candidates of opposite parties, down from 108 in 1996. 23 Republican House members are from districts Hillary carried, and 12 Dems are from districts Trump carried.
• Persistent volatility: 21 House districts that voted for Obama in '12 switched and went for Trump. 15 went Romney in '12 but Hillary last year.
• The decline of swing districts: In 1997, voters in 164 of the nation's 435 House districts were relatively split by party. Now, only 72 districts are in the same range — less than one-sixth of the House.
• Amazing stat: 78% of Democratic-leaning seats got even more Democratic, and 65% of GOP-leaning seats got even more Republican.

What it means: We are increasingly moving next to people who share our political views — and then following and sharing like-minded news on social media when our doors are closed. This can't be fixed with better redistricting laws.

See a chart from Quorum of Dem House members in the top R-trending districts, and GOP House members in the top D-trending districts.