This summer's NBA free-agency period sparked a feeding frenzy of epic proportions, with teams tossing around eight-figure contracts like parade confetti. Front offices managed to commit over $2 billion in future player salaries in just 10 days.

Why spend now? A dollar now is 58 cents later

With the salary cap set to skyrocket over the next three seasons, most teams embraced an expansive new mantra: Any contract that looks pricey in today's dollars will probably seem like a bargain in just a few years. By 2017-18, for example, a $10 million salary will be worth only $5.8 million in today's dollars (as a proportional share of the salary cap).

With the cost of NBA talent -- and thus NBA success -- about to explode, teams had an unusual opportunity to lock in future wins at a discount now.

Projecting Payroll And Wins Year Salary Cap Payroll $10M Salary

In '14-15 cash Cost Per Win '14-15 $63M $2.19B $10.0M $1.78M '15-16 $70M $2.43B $9.0M $1.98M '16-17 $89M $3.09B $7.1M $2.51M '17-18 $108M $3.75B $5.8M $3.05M

Unfortunately, some teams still managed to blow their golden opportunity this summer. Meanwhile, a handful of smart front offices just helped their clubs vault even further ahead of the pack.

Spoiler alert: The Spurs and Warriors are in a league of their own. We'll cover them here, along with two other surprise winners in the free-agency sweepstakes.

Tomorrow we'll look at teams that got much less bang for their free-agency buck, including the Thunder -- who've just made another personnel decision that may come back to haunt them -- and (more predictably) the Knicks, Nets and Kings.

What is a win worth? About $1.78 million

The first step in picking the winners and losers of free agency is to figure out each player's real value -- the amount he should be paid if his salary were directly proportional to his contribution to team success.

It's not hard to calculate the cost -- in salary terms -- of each NBA win. Teams spent $2.19 billion in cumulative salary in 2014-15, and they amassed a total of 1,230 regular-season wins. That works out to about $1.78 million per win.

So a player like Kyle Lowry, whose play was worth an estimated 10 wins for Toronto last year, has an implied real value of about $17.8 million. Of course, in three seasons, those same 10 wins will be worth much more -- over $30 million -- thanks to the escalating cap.

Real Plus-Minus (RPM) can be used to estimate the team wins attributable to each player. Specifically, RPM yields a metric called Wins Above Replacement (WAR) -- the number of wins we'd expect the player's team to forego if all of his possessions were taken instead by a typical minimum-salary "replacement player." (Since even replacement players generate about one victory per 2,000 minutes of play, we made a minor adjustment to WAR for our valuation analyses.)

How to create surplus value

If the NBA were a perfectly efficient market for player talent, every salary would closely match the player's real value.

Instead, some players are wildly overpaid, while others make far less than they deserve. For example, Kobe Bryant made over 25 times more than Draymond Green last season.

By delivering star-caliber production on a minimum-salary contract, Green created huge surplus value for the Warriors. And, not surprisingly, the most successful NBA teams are those that tend to maximize the surplus value of their rosters.

Put less politely: Elite teams often pay their players far less than their real value.

That's why, in the present analysis, we've focused on the implied surplus value of the key contracts teams have signed so far in free agency (through July 20). Specifically, we've used Predictive RPM (which draws on three seasons' worth of performance data), together with an RPM aging curve to forecast each player's RPM-based wins -- and the corresponding dollar value of those wins -- over the life of his new contract. (In the case of contracts with a player opt-out provision, we assume that players will always exercise the freedom to opt out of the final year if they are projected to generate surplus value at that point in the contract.)

The accompanying table lists the estimated surplus value added to each team by its new free agency contracts:

Estimated Surplus Value Added By Free Agents Team Contract Value Contract Cost SurplusValue Key FAs San Antonio 360.69 221.40 139.29 7 Golden State 196.29 84.50 111.79 2 Chicago 163.64 89.40 74.24 3 Milwaukee 154.55 90.60 63.95 2 Boston 103.61 69.00 34.61 3 LA Clippers 114.79 85.76 29.03 5 Cleveland 287.82 260.58 27.24 5 Portland 72.18 50.10 22.08 2 Toronto 106.03 93.00 13.03 3 Houston 68.33 57.59 10.74 4 Indiana 79.97 69.30 10.67 4 Atlanta 49.00 40.67 8.33 2 Charlotte 6.49 2.14 4.35 1 Dallas 89.18 86.40 2.78 6 Detroit 114.28 114.50 -0.22 3 Utah 2.16 4.60 -2.44 1 New Orleans 87.57 91.20 -3.63 5 Washington 3.81 9.40 -5.59 3 Minnesota 6.38 16.50 -10.12 1 Memphis 116.79 130.31 -13.52 2 Denver 4.46 24.60 -20.14 2 LA Lakers 6.24 27.00 -20.76 2 New York 72.71 94.99 -22.28 6 Phoenix 101.89 129.00 -27.11 4 Sacramento 18.62 61.78 -43.16 5 Miami 87.31 112.90 -44.16 4 Orlando 37.66 83.50 -45.84 3 OKC 21.45 89.36 -67.91 2 Brooklyn 52.53 126.92 -74.39 6

Before we explore how teams enhanced or degraded their overall surplus value through summer free agency (in Parts II and III of our series), a disclaimer: These valuation numbers are to be taken as estimates. They're not definitive.

There are two sources of potential error in each player's value estimate: (1) his Predictive RPM, which is a mathematical estimate of how the player will perform next season based on his real plus-minus impact over the past three seasons; and (2) the player's RPM estimate for every contract year beyond 2015-16, which is based on an aging curve for the typical NBA player, with an RPM impact that increases through about age 26 and then declines, ever-more-steeply, starting at about age 28 (obviously, some players age better or worse than others).

With these interpretive caveats in mind, our method of surplus value estimation can provide a useful new lens through which to view and evaluate each new contract signed during free agency -- as well as the other 350-plus contracts that make up the league's total payroll.