These days, it is rare for a TV show to grow its audience year over year, but miracles -- and sophomore smash hits like "This Is Us" -- do happen.   Thus far this season, six broadcast series are averaging more total viewers than they did at this same period in autumn last year. We've ranked them in order from smallest to largest gainers. Also Read: Cancellation Watch: 9 TV Shows That Likely Won’t Last Beyond This Season (Photos)

Show: "Chicago Fire"  Net: NBC  This season's viewer average: 10.399 million  Last season's viewer average: 10.059 million   Change: +3%   Dick Wolf drama only joined the list of growers this week. Insert your own "on Fire" joke.   Also Read: 31 Highest and Lowest-Rated Shows of the Fall TV Season So Far (Photos)

Show: "Dateline - Friday"    Net: NBC  This season's viewer average: 5.916 million  Last season's viewer average: 5.664 million   Change: +4%   As Chris Hansen would say, "Have a seat," and that's exactly what Dateline viewers are doing in front of the TV when this news magazine show is on.   Also Read: 10 Lowest-Rated TV Shows of Summer 2017 (Photos)

Show: "Bob's Burgers"  Net: Fox    This season's viewer average: 3.366 million  Last season's viewer average: 3.157 million   Change: +7%   Despite NFL's declining ratings, this animated show has benefitted more this season from some football afternoon games leading into its airing. Also Read: 11 Top-Rated TV Shows of Summer 2017 (Photos)

Show: "Chicago PD"  Net: NBC  This season's viewer average: 8.912 million  Last season's viewer average: 8.041 million   Change: +11%   There's something about this Windy City drama that has fans hooked.    Also Read: ‘Judge Judy’ Wins 2016-17 Syndicated Season, Its Fourth in a Row

Show: "This Is Us"  Net: NBC  This season's viewer average: 15.344 million  Last season's viewer average: 13.538 million   Change: +13%   This one's easy to explain -- cross-reference "Empire" Season 2 for another recent sophomore-bump example.   Also Read: 20 Highest-Rated Shows That Got Canceled Last Season (Photos)

Show: "Mom"  Net: CBS  This season's viewer average: 9.285 million  Last season's viewer average: 8.134 million  Change: +14%   Thanks, (new lead-in) "Young Sheldon"!   Also Read: The 22 Lowest-Rated Shows to Get Renewed Last Season (Photos)

Meanwhile, ABC's "America's Funniest Home Videos" was actually up 11 percent in the key 18-49 demographic, but down 3 percent among overall viewers.   Every show in this gallery not named "Chicago Fire" and "Dateline" also grew in the aforementioned demo.   Also Read: 20 Lowest-Rated TV Shows of 2016-17 Season (Photos)