The Street sold off Roku (NASDAQ:ROKU) stock after its third-quarter earnings release earlier this month, but that doesn't mean the streaming TV company isn't performing well. The pullback in Roku stock was more of a function of high expectations, not poor performance.

Zooming out beyond Roku stock's recent pullback, shares are still up 14% year over year, doubling the S&P 500's 7% gain during this same period. It's no surprise the stock has outperformed the market. Roku has delivered some impressive growth during this period. To see just how far Roku has come over the past 12 months, consider some of these key metrics from Roku's most recent earnings release.

1. Revenue increased 39%

Roku's third-quarter revenue rose 39% year over year. Highlighting the company's strong momentum, this growth is on top of 40% year-over-year revenue growth in the year-ago quarter.

2. Active accounts jumped 43%

Roku's active accounts continued to surge, rising 43% year over year in Q3. That puts total active accounts at 23.8 million.

3. Streaming hours rose 63%

Users streamed 6.2 billion hours of media during the quarter, up 63% year over year. That marked an acceleration from the 57% growth in streaming hours Roku saw in Q2.

4. Average revenue per user increased 37%

Roku's average revenue per user, which the company tracks on a trailing-12-month basis, was up 37% year over year in Q3 to $17.34. That's up from average revenue per user of $16.60 for the trailing-12-month period ended June 30.

5. Platform revenue increased 74%

Roku's platform revenue, or revenue primarily from advertising sales and from subscription and transaction revenue share, jumped 74% year over year in Q3. Showing how platform revenue is growing in importance to Roku's business, the segment now accounts for 58% of total revenue, up from 46% of revenue in the year-ago quarter.

6. More than two-thirds of platform revenue came from advertising

Roku has credited much of its strong growth to its advertising business, which now accounts for over two-thirds of the company's platform revenue and continues to grow rapidly. Sales from video ads, in particular, are growing quickly. Management said video ad sales more than doubled year over year in Q3.

Looking ahead, management is extremely bullish on the potential for further growth in advertising on its platform, calling the shift from traditional TV advertising to streaming its "largest opportunity over the long term."

7. Gross profit surged 58%

Proving the scalability of Roku's business model, the company's gross profit grew faster than revenue. Roku's third-quarter gross profit was $79 million, up 58% year over year.

With so much momentum, it's not surprising management is bullish about the company's future. Management said in Roku's third-quarter shareholder letter that it believes this is just the beginning of "the massive transition of TV viewing and TV advertising to streaming."