The chart now includes on-demand streaming and digital track sales.

The newly refreshed Billboard 200 albums chart welcomes a familiar face back to No. 1, as Taylor Swift's 1989 hops back to the top slot (2-1) after a one-week vacation. This is the album's fourth non-consecutive week at No. 1.

The Billboard 200, which has long been a chart that ranked the most popular albums of the week based on pure album sales, now shifts its methodology to a multi-metric consumption model. The ranking includes on-demand streaming and digital track sales, in addition to traditional album sales, all measured by Nielsen.

This is the most substantial update to the chart's methodology since May of 1991, when Billboard first used Nielsen's point-of-sale data — SoundScan — to measure album sales.

As previously reported, the new Billboard 200 chart uses accepted industry benchmarks for digital and streaming data, where 10 digital track sales from an album is equivalent to one album sale, and 1,500 song streams from an album equates to one album sale. All of the major on-demand audio subscription services are considered, including Spotify, Beats Music, Google Play and Xbox Music.

Swift's return to No. 1 is powered by 339,000 total album equivalent units in the week ending Nov. 30. Of that sum, the majority is pure album sales (281,000).

1989's album sales now stand at 2.5 million after five weeks on sale.

The album is also No. 1 on the Top Album Sales chart, which maintains the old Billboard 200's methodology of ranking pure album sales.

Swift continues to ride high on the Digital Songs chart, where she has two songs in the top 10: "Blank Space" (holding at No. 1, with 342,000 downloads; up 13 percent) and "Shake It Off" (8-10 with 93,000; up 12 percent).