As expected, the FCC's 24 GHz spectrum auction blew past the $1 billion mark Friday (March 22) only seven business days after it began (March 14).

The total as of round 20 was $1,093,9921,875. By comparison, the previous high-band millimeter-wave spectrum auction (28 GHz) closed with a little over $700 billion in bids over nine weeks.

The FCC is auctioning the spectrum to free up more bandwidth for 5G wireless broadband, to help close the rural digital divide, and to make wireless a stronger competitor to wired broadband.

New York and L.A. continue to lead, with bids on licenses there of $28,080,000 and $21,606,000, respectively, with Chicago in distant third with $10,436,000.

The millimeter-wave (high-band) auction opened March 14 and is being held in two phases. Initial bidding (clock phase) is on generic spectrum, with a follow-on auction (assignment phase) among the winners for specific frequencies.

Related: FCC Launches Latest 5G Auction

The clock auction means the FCC continues to raise prices automatically after each round, so long as there is more demand than supply, until there are not bidders left, high bidder at that point wins.

Bidding is currently in three, one-hour rounds, but the FCC could boost the number of rounds or shorten their duration if and when it wants to goose the bidding.

The initial license periods are not to exceed 10 years. There are also build-out requirements—so the spectrum can't be warehoused but must be used as advertised. Bidding credits were available for rural service, small businesses and tribal lands, capped at $25 million.

The 24 GHz spectrum is divided into a lower and higher portion, the lower (24.25 – 24.45 GHz and 24.75 – 25.25 GHz) being licenses as two, 100-MHz blocks and the upper (24.75 – 25.25 GHz) licenses as five, 100 MHz blocks.

The 28 GHz spectrum auction, the first millimeter-wave auction, in $702,572,410 for 2,965 licenses. The 24 GHz auction comprises 2,909 licenses divided up by partial economic areas.

And the FCC isn't done. FCC Chairman Ajit Pai announced last week that the FCC next month will release a public notice seeking comment on the third millimeter-wave spectrum band auction of the year.