Hockey is a game of momentum. It can switch in the middle of a shift or over the course of a season.
Early in the 2014-15 campaign, we’ve seen certain players and teams gather momentum, while others struggle and fail to live to expectations.
So, in the first installment of our NHL Stock Report, here are some things across the league trending up and others that are trending down.
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TRENDING UP: That 70s Line 
Jeff Carter, Tyler Toffoli and Tanner Pearson haven’t missed a beat. The trio has maintained the chemistry they developed and honed during their spring Stanley Cup run. They’ve been arguably the best line in hockey this season, posting a combined 12 goals, 23 points and a plus-25 rating through seven games. Even though they’re not the Kings’ top unit—that distinction goes to whichever line Anze Kopitar is centring—they’re playing like a first line. No. 77, No. 73 and No. 70 haven’t shown any signs they’re going to slow down anytime soon.
TRENDING UP: Patric Hornqvist and Penguins’ PP
The Penguins finally found a right-handed shot that can play with Sidney Crosby and Chris Kunitz. Patric Hornqvist has found instant chemistry with the two 2014 Olympic gold medallists, which is exactly what GM Jim Rutherford envisioned when he brought in the talented Swede from Nashville in a trade that sent James Neal to the Predators in late June. Last season, Hornqvist set a career high with 53 points in 76 games, and he’s currently on pace to shatter that total.
In addition to having an outstanding name, Penguins head coach Mike Johnston also has a team that can be as dominant as the Harlem Globetrotters when they’ve got the man advantage. They possess the best power play in the league without question, and Hornqvist, who’s not afraid to get dirty in front of the net, is a big part of it. Yes, it’s early in the season, but they’re operating at an astounding 36.4 per cent through six games.
TRENDING UP: Barry Trotz
Trotz is slowly transforming a group of talented, dynamic skaters that often played like individuals into a cohesive unit. And when you consider what the Washington Capitals are capable of in the offensive zone, that’s a scary prospect for the rest of the Eastern Conference. The Capitals were consistently outplayed at even strength last season, but they’ve been one of the best five-on-five teams out of the gate in 2014-15. Another significant sign of Trotz’s impact in Washington has been the play of Alex Ovechkin. The Great 8 has five goals in his first six games, which isn’t surprising, but what is a bit of a shock is his even plus/minus rating, a stark improvement from last season, when he finished a dreadful minus-35. According to Ovechkin, the culture in the Capitals’ locker room has changed for the better and that’s a credit to Trotz.
TRENDING UP: T.J. Brodie’s bank account
Calgary’s standout blueliner received a five-year, $23.25-million contract extension. It’s a well-deserved deal, which doesn’t kick in until next season, for the 24-year-old Chatham, Ont., native. A $4.65-million cap hit (the second highest on the team next to Dennis Wideman’s $5.2-million tag) might seem like a steep price for a defenceman who for the time being lacks star power, but as Elliotte Friedman pointed out, players like Brodie are few and far between.
TRENDING UP: North American hockey camaraderie 
A heartfelt hat tip to American NHL teams that honoured Canada with moments of silence and renditions of O Canada following the shooting on Parliament Hill that stunned the world.
The tragedy had nothing to do with sports, but these types of gestures mean a great deal to people regardless of setting.
Trend to watch for: After dropping their first five games, the Oilers rebounded with back-to-back 3-2 wins over the Lightning and Capitals. Things could finally be turning around in Edmonton if Ben Scrivens can keep up his solid play.
TRENDING DOWN: The Buffalo Sabres’ goal light
Through the first eight games, the Sabres registered just eight goals. To put that in perspective, Rick Nash and Corey Perry have eight goals each, and they both managed to do it in one fewer game. Connor McDavid had a goal and three assists as the Erie Otters beat the Niagara IceDogs 8-4 at the First Niagara Center Wednesday. Meanwhile, the Sabres have generated a mere two goals there in four home games. The silver lining for Sabres fans? If things continue down this path, there’s a great chance McDavid will generate more points at the First Niagara Center next season as well.
TRENDING DOWN: The Boston Bruins 
The Bruins have boasted one of the best blue-lines in hockey the last five seasons, but things look rough at the moment. Captain Zdeno Chara will miss four to six weeks with a knee injury, and seeing Johnny Boychuk enjoy early success with the Islanders rubs salt in the wound.
TRENDING DOWN: Off-season naysayers
OK, the Sabres and Hurricanes appear to be as bad as most thought they’d be, and the Corsi nerds are tooting their horns at Colorado’s slow start, but teams like the Predators, Senators and Flames have impressed early in 2014-15 despite essentially being dismissed as non-factors before the season began. Heading into Friday’s action, those three teams had as many or more points than the Bruins, Blues, Penguins, Wild, Stars and Rangers—clubs viewed as contenders in their respective divisions. The Predators, Senators and Flames play hard, simple hockey and outwork their opponents. These teams are proving that little things go a long way in hockey, and it goes to show that even if a team lacks star power, you can’t underestimate heart and grit.
TRENDING DOWN: Phil Kessel jokes
This stock will always trend higher than most because Phil the Thrill is one of the most compelling, funny (whether intentional or not) and interesting players in the NHL. Prior to the season, Kessel was lambasted for admitting he only skated a handful of times and he’s often criticized for his un-Herculean appearance. However, when he’s flying down the right wing and firing pucks past helpless goalies, like he did twice against Jaroslav Halak this week, jokes about his physique have no zing–unlike the condiments he puts on his off-season hot dogs.
TRENDING DOWN: Luongo’s Twitter game
Roberto Luongo is the NHL’s best tweeter. That’s undisputed. But since puck drop on opening night he has only tweeted once, and it wasn’t even hockey-related–it was about Peyton Manning.
We get that you’re focused on playing well and helping the Florida Panthers contend for a playoff spot, but come on, Roberto, throw us a bone… a Strombone.
Trend to watch for: The St. Louis Blues have underwhelmed early. Paul Stastny is injured, and the Blues’ next three games are against the Blackhawks, Stars and Ducks.