Table:
|  |  |  | Years Ended December 31, |  |  |
| --- | --- | --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 | 2016 | 2015 |
|  |  |  | (In thousands, except per share amounts) |  |  |
| Net sales . | $3,063,117 | $2,244,044 | $2,941,324 | $2,904,563 | $4,112,650 |
| Gross profit | 549,212 | 392,177 | 548,947 | 638,418 | 1,132,762 |
| Operating (loss) income . | (161,785) | 40,113 | 177,851 | (568,151) | 730,159 |
| Net (loss) income | (114,933) | 144,326 | (165,615) | (416,112) | 593,406 |
| Net (loss) income per share: |  |  |  |  |  |
| Basic . | $(1.09) | $1.38 | $(1.59) | $(4.05) | $5.88 |
| Diluted . | $(1.09) | $1.36 | $(1.59) | $(4.05) | $5.83 |
| Cash dividends declared per common share. | $— | $— | $— | $— | $— |
| Net cash provided by (used in) operating |  |  |  |  |  |
| activities | $174,201 | $(326,809) | $1,340,677 | $206,753 | $(325,209) |
| Net cash (used in) provided by investing |  |  |  |  |  |
| activities | (362,298) | (682,714) | (626,802) | 144,520 | (156,177) |
| Net cash provided by (used in) financing |  |  |  |  |  |
| activities | 74,943 | 255,228 | 192,045 | (136,393) | 101,207 |
|  |  |  | December 31, |  |  |
|  | 2019 | 2018 | 2017 | 2016 | 2015 |
|  |  |  | (In thousands) |  |  |
| Cash and cash equivalents . | $1,352,741 | $1,403,562 | $2,268,534 | $1,347,155 | $1,126,826 |
| Marketable securities . | 811,506 | 1,143,704 | 720,379 | 607,991 | 703,454 |
| Total assets . | 7,515,689 | 7,121,362 | 6,864,501 | 6,824,368 | 7,360,392 |
| Total long-term debt | 471,697 | 466,791 | 393,540 | 188,388 | 289,415 |
| Total liabilities | 2,418,922 | 1,908,959 | 1,765,804 | 1,606,019 | 1,741,996 |
| Total stockholders’ equity . | 5,096,767 | 5,212,403 | 5,098,697 | 5,218,349 | 5,618,396 |
Paragraphs:
Item 6. Selected Financial Data
The following tables set forth our selected financial data for the periods and at the dates indicated. The selected financial data from the consolidated statements of operations and consolidated statements of cash flows for the years ended December 31, 2019, 2018, and 2017 and the selected financial data from the consolidated balance sheets as of December 31, 2019 and 2018 have been derived from the audited consolidated financial statements included in this Annual Report on Form 10-K. The selected financial data from the consolidated statements of operations and consolidated statements of cash flows for the years ended December 31, 2016 and 2015 and the selected financial data from the consolidated balance sheets as of December 31, 2017, 2016, and 2015 have been derived from audited consolidated financial statements not included in this Annual Report on Form 10-K. The information presented below should also be read in conjunction with our consolidated financial statements and the related notes thereto and Item 7. “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”
Question:
What was the percentage increase in gross profit from 2018 to 2019?
Answer: (549212 - 392177) / 392177  = 40.04