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Consolidated Statements of Operations - USD ($) | 12 Months Ended
--- | ---
Jun. 30, 2015 | Jun. 30, 2014 | Jun. 30, 2013
Revenues |  |  |  |
Total revenues |  | $ 27,841,265 | $ 17,673,508 | $ 21,349,920
Operating costs |  |  |  |
Depreciation, depletion and amortization |  | 3,615,737 | 1,228,685 | 1,300,207
Accretion of discount on asset retirement obligations |  | 34,866 | 41,626 | 72,312
General and administrative expenses | [1] | 6,256,783 | 8,388,291 | 7,495,309
Restructuring charges | [2] | (5,431) | 1,293,186 | 0
Total operating costs |  | 19,257,568 | 12,145,361 | 10,648,566
Income from operations |  | 8,583,697 | 5,528,147 | 10,701,354
Other |  |  |  |
(Loss) on derivative instruments, net |  | (109,974) | 0 | 0
Interest income |  | 35,991 | 30,256 | 22,580
Interest (expense) |  | (73,636) | (69,092) | (65,745)
Income before income tax provision |  | 8,436,078 | 5,489,311 | 10,658,189
Income tax provision |  | 3,444,221 | 1,891,998 | 4,029,761
Net income attributable to the Company |  | 4,991,857 | 3,597,313 | 6,628,428
Dividends on preferred stock |  | 674,302 | 674,302 | 674,302
Net income attributable to common shareholders |  | $ 4,317,555 | $ 2,923,011 | $ 5,954,126
Earnings per common share |  |  |  |
Basic (in dollars per share) |  | $ 0.13 | $ 0.09 | $ 0.21
Diluted (in dollars per share) |  | $ 0.13 | $ 0.09 | $ 0.19
Weighted average number of common shares outstanding |  |  |  |
Basic (in shares) |  | 32,817,456 | 30,895,832 | 28,205,467
Diluted (in shares) |  | 32,924,018 | 32,564,067 | 31,975,131
Delhi Field |  |  |  |
Revenues |  |  |  |
Total revenues |  | $ 27,573,641 | $ 16,908,666 | $ 19,219,036
Operating costs |  |  |  |
Production costs |  | 8,516,323 | 0 | 0
Artificial Lift Technology |  |  |  |
Revenues |  |  |  |
Total revenues |  | 247,255 | 623,332 | 375,063
Operating costs |  |  |  |
Production costs |  | 743,802 | 609,221 | 390,238
Other Property |  |  |  |
Revenues |  |  |  |
Total revenues |  | 20,369 | 141,510 | 1,755,821
Operating costs |  |  |  |
Production costs |  | $ 95,488 | $ 584,352 | $ 1,390,500
[1] | General and administrative expenses for the years ended June 30, 2015, 2014 and 2013 included non-cash stock-based compensation expense of $943,653, $1,352,322, and $1,531,745, respectively.
[2] | Restructuring charges for the year ended June 30, 2014 included non-cash stock-based compensation expense of $376,365.

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