| Population Projection Series | |||||||||||||||
| June 29, 2000 | |||||||||||||||
| New Castle County | |||||||||||||||
| Total Population | |||||||||||||||
| [As of July 1] | |||||||||||||||
| 1990 | 1991 | 1992 | 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 | 2005 | 2010 | 2015 | 2020 | |
| 0 - 4 | 32723 | 33158 | 33460 | 33480 | 33509 | 33138 | 32737 | 32541 | 32377 | 32163 | 31978 | 30244 | 28838 | 28672 | 29075 |
| 5 - 9 | 30423 | 30760 | 30993 | 31154 | 31566 | 31741 | 32040 | 32335 | 32409 | 32559 | 32673 | 30732 | 29039 | 27611 | 27500 |
| 10 - 14 | 28008 | 28797 | 29513 | 30065 | 30632 | 30834 | 31042 | 31279 | 31513 | 31716 | 31939 | 33013 | 30998 | 29193 | 27794 |
| 15 - 19 | 31085 | 29920 | 29386 | 29330 | 29524 | 29725 | 30465 | 31238 | 31908 | 32633 | 33347 | 32914 | 33975 | 31792 | 29982 |
| 20 - 24 | 38450 | 38320 | 37681 | 36539 | 35200 | 33948 | 32788 | 32344 | 32381 | 32149 | 32061 | 36031 | 35500 | 36570 | 34316 |
| 25 - 29 | 40609 | 40588 | 40296 | 40045 | 39951 | 40204 | 39956 | 39240 | 38123 | 37198 | 36220 | 34503 | 38809 | 38060 | 39291 |
| 30 - 34 | 41338 | 42007 | 42382 | 42595 | 42752 | 42928 | 42771 | 42394 | 42081 | 41703 | 41372 | 37647 | 35672 | 39929 | 39271 |
| 35 - 39 | 35720 | 37314 | 38951 | 40611 | 42161 | 43756 | 44327 | 44643 | 44775 | 44951 | 45108 | 44035 | 40034 | 37742 | 42295 |
| 40 - 44 | 31788 | 33175 | 33641 | 34555 | 35587 | 36830 | 38322 | 39918 | 41483 | 43112 | 44807 | 45996 | 45068 | 40801 | 38431 |
| 45 - 49 | 25071 | 25981 | 27774 | 29003 | 30305 | 31759 | 33039 | 33429 | 34224 | 34799 | 35510 | 44791 | 45903 | 44888 | 40688 |
| 50 - 54 | 20139 | 20848 | 21658 | 22682 | 23516 | 24386 | 25196 | 26885 | 27990 | 29468 | 30853 | 34071 | 42970 | 43844 | 43085 |
| 55 - 59 | 18976 | 18817 | 18690 | 18735 | 18776 | 18841 | 19416 | 20135 | 21003 | 21819 | 22714 | 28331 | 31240 | 39316 | 40121 |
| 60 - 64 | 18825 | 18641 | 18317 | 17922 | 17521 | 17263 | 17049 | 16921 | 16929 | 16850 | 16818 | 20055 | 24975 | 27451 | 34685 |
| 65 - 69 | 17680 | 17472 | 17323 | 17248 | 17008 | 16838 | 16650 | 16344 | 15992 | 15654 | 15321 | 14295 | 17005 | 21133 | 23179 |
| 70 - 74 | 13296 | 13890 | 14424 | 14845 | 15291 | 15572 | 15405 | 15193 | 15061 | 14878 | 14727 | 13596 | 12663 | 15044 | 18726 |
| 75 - 79 | 9369 | 9618 | 9928 | 10153 | 10401 | 10724 | 11158 | 11524 | 11834 | 12173 | 12514 | 11347 | 10467 | 9741 | 11596 |
| 80 - 84 | 5707 | 5879 | 6070 | 6269 | 6480 | 6729 | 6896 | 7114 | 7310 | 7520 | 7735 | 9093 | 8225 | 7569 | 7032 |
| 85 & up | 4337 | 4492 | 4592 | 4698 | 4845 | 4957 | 5127 | 5266 | 5415 | 5558 | 5712 | 6084 | 6970 | 6756 | 6403 |
| Totals | 443544 | 449677 | 455079 | 459929 | 465025 | 470173 | 474384 | 478743 | 482808 | 486903 | 491409 | 506778 | 518351 | 526112 | 533470 |