| Schedule of Cash and Cash Equivalents and Short-Term Investments by Significant Investment Category |
The following tables show the Company’s cash and cash equivalents and short-term investments by significant investment category as of June 30, 2018 and December 31, 2017:
|
|
|
June 30, 2018 |
|
|
|
|
Amortized Cost |
|
|
Gross Unrealized Losses |
|
|
Estimated Fair Value |
|
|
Cash and Cash Equivalents |
|
|
Short-Term Investments |
|
|
Cash |
|
$ |
2,472,787 |
|
|
$ |
— |
|
|
$ |
2,472,787 |
|
|
$ |
2,472,787 |
|
|
$ |
— |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Level 1 (1): |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds |
|
|
4,766,639 |
|
|
|
— |
|
|
|
4,766,639 |
|
|
|
4,766,639 |
|
|
|
— |
|
|
U.S. treasury securities |
|
|
2,500,905 |
|
|
|
(2,297 |
) |
|
|
2,498,608 |
|
|
|
— |
|
|
|
2,498,608 |
|
|
Subtotal |
|
|
7,267,544 |
|
|
|
(2,297 |
) |
|
|
7,265,247 |
|
|
|
4,766,639 |
|
|
|
2,498,608 |
|
|
Level 2 (2): |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Commercial paper |
|
|
9,701,381 |
|
|
|
— |
|
|
|
9,701,381 |
|
|
|
2,246,170 |
|
|
|
7,455,211 |
|
|
Corporate debt obligations |
|
|
5,323,767 |
|
|
|
(2,059 |
) |
|
|
5,321,708 |
|
|
|
773,432 |
|
|
|
4,548,276 |
|
|
Repurchase agreements |
|
|
3,000,329 |
|
|
|
— |
|
|
|
3,000,329 |
|
|
|
3,000,329 |
|
|
|
— |
|
|
Asset-backed securities |
|
|
4,319,154 |
|
|
|
(3,594 |
) |
|
|
4,315,560 |
|
|
|
— |
|
|
|
4,315,560 |
|
|
Subtotal |
|
|
22,344,631 |
|
|
|
(5,653 |
) |
|
|
22,338,978 |
|
|
|
6,019,931 |
|
|
|
16,319,047 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
32,084,962 |
|
|
$ |
(7,950 |
) |
|
$ |
32,077,012 |
|
|
$ |
13,259,357 |
|
|
$ |
18,817,655 |
|
|
|
|
December 31, 2017 |
|
|
|
|
Amortized Cost |
|
|
Gross Unrealized Losses |
|
|
Estimated Fair Value |
|
|
Cash and Cash Equivalents |
|
|
Short-Term Investments |
|
|
Cash |
|
$ |
3,040,696 |
|
|
$ |
— |
|
|
$ |
3,040,696 |
|
|
$ |
3,040,696 |
|
|
$ |
— |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Level 1 (1): |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Money market funds |
|
|
8,234,751 |
|
|
|
— |
|
|
|
8,234,751 |
|
|
|
8,234,751 |
|
|
|
— |
|
|
U.S. treasury securities |
|
|
2,490,799 |
|
|
|
(5,540 |
) |
|
|
2,485,259 |
|
|
|
— |
|
|
|
2,485,259 |
|
|
Subtotal |
|
|
10,725,550 |
|
|
|
(5,540 |
) |
|
|
10,720,010 |
|
|
|
8,234,751 |
|
|
|
2,485,259 |
|
|
Level 2 (2): |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Commercial paper |
|
|
9,716,093 |
|
|
|
— |
|
|
|
9,716,093 |
|
|
|
— |
|
|
|
9,716,093 |
|
|
Corporate debt obligations |
|
|
6,829,191 |
|
|
|
(9,414 |
) |
|
|
6,819,777 |
|
|
|
— |
|
|
|
6,819,777 |
|
|
Repurchase agreements |
|
|
3,000,233 |
|
|
|
— |
|
|
|
3,000,233 |
|
|
|
3,000,233 |
|
|
|
— |
|
|
Asset-backed securities |
|
|
3,018,276 |
|
|
|
(1,953 |
) |
|
|
3,016,323 |
|
|
|
750,388 |
|
|
|
2,265,935 |
|
|
Subtotal |
|
|
22,563,793 |
|
|
|
(11,367 |
) |
|
|
22,552,426 |
|
|
|
3,750,621 |
|
|
|
18,801,805 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total |
|
$ |
36,330,039 |
|
|
$ |
(16,907 |
) |
|
$ |
36,313,132 |
|
|
$ |
15,026,068 |
|
|
$ |
21,287,064 |
|
|
|
(1) |
Level 1 fair value estimates are based on quoted prices in active markets for identical assets or liabilities. |
|
|
(2) |
Level 2 fair value estimates are based on observable inputs other than quoted prices in active markets for identical assets and liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. |
|