| Middletown Springs - Population Change | FIPS Code=21055 |
| Absolute Population Change, 1970-1980 | 177 |
| Per Cent Population Change, 1970-1980 | 41.55 |
| Absolute Population Change, 1980-1990 | 83 |
| Per Cent Population Change, 1980-1990 | 13.76 |
| Population Estimate, 1996 | 708 |
| Population Estimate, 2000 | 803 |
| Population Estimate, 2005 | 846 |
| Population Estimate, 2010 | 891 |
| Population Estimate, 2015 | 927 |
| Absolute Population Change, 1990-1996 | #REF! |
| Per Cent Population Change, 1990-1996 | 3.21 |
| Absolute Population Change, 1996-2005 | 138 |
| Per Cent Population Change, 1996-2005 | 19.49 |
| Absolute Population Change, 2005-2015 | 81 |
| Per Cent Population Change, 2005-2015 | 9.57 |