SB 25-180
Fiscal Note
Legislative Council Staff
Nonpartisan Services for Colorado’s Legislature
SB 25-180: POPULATION GROWTH CALCULATION
Prime Sponsors:
Sen. Kirkmeyer; Amabile
Rep. Taggart; Sirota
Published for: Senate Appropriations
Drafting number: LLS 25-0866
Fiscal Analyst:
Elizabeth Ramey, 303-866-3522
elizabeth.ramey@coleg.gov
Version: Initial Fiscal Note
Date: February 25, 2025
Fiscal note status: This fiscal note reflects the introduced bill, which was recommended by the Joint
Budget Committee.
Summary Information
Overview. When calculating the TABOR limit population growth factor, the bill requires that the State
Controller use the base year population estimate published in that year, rather than the revised estimate
published in the following year.
Types of impacts. The bill is projected to affect the following areas on an ongoing basis:
TABOR Refunds
Appropriations. No appropriation is required.
Table 1
State Fiscal Impacts
Type of Impact
Current Year
FY 2024-25
Budget Year
FY 2025-26
Out Year
FY 2026-27
State Revenue $0 $0 $0
State Expenditures $0 $0 $0
Transferred Funds $0 $0 $0
Change in TABOR Refunds -$18.1 million -$95.2 million Indeterminate
Change in State FTE 0.0 FTE 0.0 FTE 0.0 FTE
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February 25, 2025 SB 25-180
Summary of Legislation
The state TABOR limit is adjusted each fiscal year for inflation and the percentage change in the
state’s population in the most recent calendar year. For example, the FY 2024-25 TABOR limit is
adjusted for inflation and population growth that occurred in 2023, and the FY 2025-26 TABOR
limit will be adjusted for inflation and population growth that occurred in 2024.
Under current law, population growth is calculated by comparing the U.S. Census Bureau’s
estimate of the state’s population for the growth year to its revised estimate of the state’s
population for the base year. For example, under current law, 2024 population growth is
calculated by comparing the Census Bureau’s 2024 estimate of the 2024 population to its 2024
estimate of the 2023 population.
Beginning for FY 2024-25, the bill changes the population growth calculation to use the
estimate of the base year population produced in the base year. For example, under the bill,
2024 population growth would be calculated by comparing the Census Bureau’s 2024 estimate
of the 2024 population to its 2023 estimate of the 2023 population.
Background
The calculation of the TABOR limit under current law uses the most recent estimate of
population for both the base year and the growth year. As a result, the calculation does not
incorporate changes to the population estimate that occur between the initial estimate used to
set one fiscal year’s limit, and the revised estimate used to set the next fiscal year’s limit. This
means that revised population estimates trigger either an undercount (in the case of an upward
revision) or a double-count (in the case of a downward revision) in the level of the next fiscal
year’s limit. This effect is discussed in more detail in a January 28, 2025, Legislative Council Staff
research memorandum.
1
TABOR Refunds
The bill has a bidirectional effect on the level of the TABOR limit and, in years when state
revenue exceeds the limit, on TABOR refunds. In fiscal years that follow calendar years when the
population estimate is revised up, the bill increases the limit and decreases refunds. In fiscal
years that follow calendar years when the population estimate is revised down, the bill decreases
the limit and increases refunds.
1
https://leg.colorado.gov/publications/population-component-tabor-limit-growth-factor Page 3
February 25, 2025 SB 25-180
The bill is expected to result in a higher limit and decrease refunds by $18.1 million in the
current FY 2024-25 (Table 2A) and by $95.2 million in FY 2025-26 (Table 2B). The bill’s impact for
FY 2026-27 and later years depends on the direction in which population estimates are revised.
Additionally, in future years when revenue falls below the TABOR limit, the bill will have no
impact on TABOR refunds. TABOR refunds are paid from the General Fund, and decreased
refunds increase the amount available for the General Fund budget.
Table 2A
FY 2024-25 TABOR Limit Calculation Under Current Law and SB 25-180
Value Current Law SB 25-180
2022 Population Used for Growth Factor 5,841,039 5,839,926
2023 Population Used for Growth Factor 5,877,610 5,877,610
Population Component of Growth Factor 0.63% 0.65%
Inflation Component of Growth Factor 5.22% 5.22%
TABOR Limit Growth Factor (rounded to nearest tenth) 5.8% 5.9%
FY 2023-24 TABOR Limit (Referendum C Cap) $18,073.2 million $18,073.2 million
FY 2024-25 TABOR Limit (Referendum C Cap) $19,121.4 million $19,139.5 million
Change in TABOR Refunds from Current Law $0 -$18.1 million
Table 2B
FY 2025-26 TABOR Limit Calculation Under Current Law and SB 25-180
Value Current Law SB 25-180
2023 Population Used for Growth Factor 5,901,339 5,877,610
2024 Population Used for Growth Factor 5,957,493 5,957,493
Population Component of Growth Factor 0.95% 1.36%
Inflation Component of Growth Factor 2.27% 2.27%
TABOR Limit Growth Factor (rounded to nearest tenth) 3.2% 3.6%
FY 2024-25 TABOR Limit (Referendum C Cap) $19,121.4 million $19,139.5 million
FY 2025-26 TABOR Limit (Referendum C Cap) $19,731.5 million $19,826.7 million
Change in TABOR Refunds from Current Law $0 -$95.2 million
Effective Date
The bill takes effect upon signature of the Governor, or upon becoming law without his
signature. Page 4
February 25, 2025 SB 25-180
State and Local Government Contacts
Legislative Council Staff Economics Section
Personnel
State Auditor
The revenue and expenditure impacts in this fiscal note represent changes from current law under the bill for each
fiscal year. For additional information about fiscal notes, please visit the General Assembly website.