Stockholders' Equity (Tables)
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9 Months Ended |
Sep. 30, 2018 |
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| Equity [Abstract] |
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| Summary of Stock Options Activity |
The activity for stock options under the Company’s stock plans is as follows:
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Remaining
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weighted-
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Weighted-
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average
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Per share
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average
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contractual
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average
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Price per
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exercise
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terms
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intrinsic
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Options
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share
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price
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(in years)
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value
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Outstanding as of December 31, 2017
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1,836,426
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$0.60-$83.30
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$
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30.77
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4.58
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$
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88.31
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Granted
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—
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—
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—
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Exercised
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(434,724
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0.60-58.95
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25.22
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Forfeited
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(625
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24.52
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24.52
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Expired
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—
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—
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—
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Outstanding as of September 30, 2018
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1,401,077
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$0.75-$83.30
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$
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32.50
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4.03
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$
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211.62
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Vested and exercisable as of September 30, 2018
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1,048,407
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$0.75-$83.30
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$
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28.95
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3.93
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$
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215.17
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Vested and expected to vest as of September 30, 2018
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1,377,950
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$0.75-$83.30
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$
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32.32
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4.03
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$
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211.80
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| Summary of Restricted Stock Activity |
Stock Awards activity for the nine months ended September 30, 2018, is summarized below:
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Weighted-
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average
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grant
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Performance
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date fair
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and
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value
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Time-based
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time-based
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Total
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per share
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Unvested restricted stock units outstanding as of December 31, 2017
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42,028
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13,109
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55,137
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$
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90.05
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Granted
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30,033
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—
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30,033
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143.19
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Vested
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(11,002
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(4,370
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(15,372
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89.05
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Forfeited/canceled
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(1,452
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—
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(1,452
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104.81
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Unvested restricted stock units outstanding as of September 30, 2018 (1)
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59,607
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8,739
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68,346
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$
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113.32
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Unvested and expected to vest restricted stock units outstanding as
of September 30, 2018
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63,449
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$
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114.10
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Unvested restricted stock awards outstanding as of December 31, 2017
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20,789
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20,785
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41,574
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$
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91.52
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Granted
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22,645
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33,964
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56,609
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130.89
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Vested
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(5,198
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(6,928
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(12,126
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91.52
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Forfeited/canceled
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—
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—
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—
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—
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Unvested restricted stock awards outstanding as of September 30, 2018 (1)
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38,236
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47,821
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86,057
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$
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115.38
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Unvested and expected to vest restricted stock awards outstanding as
of September 30, 2018
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68,621
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$
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115.77
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(1)
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Outstanding restricted stock units and restricted stock awards are based on the maximum payout of the targeted number of shares.
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| Summary of Stock-based Compensation Expense |
Stock-based compensation
Stock-based compensation expense recognized for the three months and nine months ended September 30, 2018 and September 30, 2017 was as follows:
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Three months ended
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Nine months ended
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September 30,
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September 30,
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2018
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2017
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2018
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2017
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Stock-based compensation expense by type of award:
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Stock option plan awards
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$
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1,348
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$
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2,012
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$
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4,847
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$
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5,811
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Restricted stock units and restricted stock awards
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1,679
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402
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4,334
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450
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Employee stock purchase plan
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189
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109
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602
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369
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Total stock-based compensation expense
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$
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3,216
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$
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2,523
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$
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9,783
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$
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6,630
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For the three months and nine months ended September 30, 2018 and September 30, 2017, stock-based compensation expense recognized under ASC 718, included in cost of revenue, research and development expense, sales and marketing expense, and general and administrative expense, was as follows:
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Three months ended
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Nine months ended
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September 30,
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September 30,
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2018
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2017
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2018
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2017
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Cost of revenue
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$
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187
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$
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205
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$
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719
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$
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608
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Research and development
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348
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260
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1,010
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733
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Sales and marketing
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630
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407
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1,761
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1,069
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General and administrative
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2,051
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1,651
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6,293
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4,220
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Total stock-based compensation expense
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$
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3,216
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$
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2,523
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$
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9,783
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$
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6,630
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