Colorado · TABOR
The TABOR limit against the revenue it limits
From FY 1992-93 to FY 2024-25, Colorado’s revenue subject to TABOR grew +284%. Inflation plus population growth, compounded over the same years, allowed +314%. Over the whole run, revenue did not outgrow the formula. The state still owed refunds in 14 years, because the limit is set in dollars each year, not by the long-run rate.
Inflation plus population, compounded, same years
+314%
Each year’s allowed growth rate as the schedule used it, multiplied year on year. CALC
Refunds owed, all certified years
$13.33B
14 years with a refund. Each year’s own surplus, counted once. CALC
Kept under Referendum C, years printed
$33.46B
3 refund years under the cap print no kept figure, so this is a floor. CALC
Why some years had a refund
FACTA refund depends on dollars, not on the growth rate. Each year’s limit grows from last year’s limit, or from last year’s revenue when revenue fell short. So a fast-growing year can owe nothing when the year before sat well under the limit. A modest year can owe a refund when revenue was already at the limit.
- FY 1993-94 to FY 2004-05: the TABOR limitRevenue above the limit was refunded.
- FY 2005-06 to FY 2009-10: the Referendum C time-outVoters let the state keep all revenue for five years. No refunds, even in the 3 years revenue was above the limit.
- FY 2010-11 on: the Referendum C capA higher cap replaced the limit. Revenue above the cap is refunded. Revenue between the old limit and the cap is kept.
- Above the limit: refunded
- Above the limit in the time-out: kept
- Below the limit: no refund
This chart is drawn from the data file. Every figure in it is in the table below.
What Referendum C did
Voters approved Referendum C in 2005. It was a five-year time-out: the state kept all revenue from FY 2005-06 through FY 2009-10, whatever the limit said. From FY 2010-11 it set a permanent, higher cap, which grows each year by the same inflation-plus-population rate.
The TABOR limit is still worked out every year. The space between it and the cap is revenue the state keeps. Only revenue above the cap is refunded.
The allowed growth rate is last calendar year’s inflation in the Denver area plus the state’s population growth. The line is how much revenue subject to TABOR grew from the year before.
- Inflation
- Population growth
- Revenue growth
- Refund year
- Shaded: the Referendum C time-out
This chart is drawn from the data file. Every figure in it is in the table below.
In dollars: revenue against the two limits
FACTThe TABOR limit grows from the lower of last year’s limit or last year’s revenue, so a recession lowers it for good. From FY 2010-11 the limit that decides a refund is the higher Referendum C cap. Revenue between the TABOR limit and the cap is kept, as voters approved.
- Revenue subject to TABOR
- TABOR limit (dashed)
- Referendum C cap
- Refund year
- Shaded: the Referendum C time-out
This chart is drawn from the data file. Every figure in it is in the table below.
Dollars in millions; a figure in parentheses is under the limit. Revenue growth CALC is worked out from the revenue column. Every other figure FACT is as printed in the source on its row. A dash means the figure does not apply to that year.
| Fiscal year | Limit in force | Inflation % | Population % | Allowed growth % | Revenue ($M) | Revenue growth % | TABOR limit ($M) | Ref C cap ($M) | Over (under) limit ($M) | Refund owed ($M) | Kept under Ref C ($M) | Status | Note | Source |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| FY 1992-93 | Base year | – | – | – | 5,069.7 | – | – | – | – | – | – | Actual | – | Colorado Economic Perspective, First Quarter FY 1998 (opens in a new tab) |
| FY 1993-94 | TABOR limit | 3.7 | 2.8 | 6.5 | 5,385.1 | 6.2 | 5,399.2 | – | (14.1) | 0.0 | – | Actual | – | Colorado Economic Perspective, First Quarter FY 1998 (opens in a new tab) |
| FY 1994-95 | TABOR limit | 4.2 | 3.0 | 7.2 | 5,757.3 | 6.9 | 5,767.5 | – | (10.2) | 0.0 | – | Actual | – | Colorado Economic Perspective, First Quarter FY 1998 (opens in a new tab) |
| FY 1995-96 | TABOR limit | 4.4 | 2.7 | 7.1 | 6,124.3 | 6.4 | 6,160.3 | – | (36.0) | 0.0 | – | Actual | – | Colorado Economic Perspective, First Quarter FY 1998 (opens in a new tab) · document 2 (opens in a new tab) · document 3 (opens in a new tab) |
| FY 1996-97 | TABOR limit | 4.3 | 2.3 | 6.6 | 6,647.6 | 8.5 | 6,508.6 | – | 139.0 | 139.0 | – | Actual | – | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 30, 1997 (and Notes) (opens in a new tab) |
| FY 1997-98 | TABOR limit | 3.5 | 2.0 | 5.5 | 7,435.2 | 11.8 | 6,872.0 | – | 563.2 | 563.2 | – | Actual | – | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 1998 (opens in a new tab) · document 2 (opens in a new tab) |
| FY 1998-99 | TABOR limit | 3.3 | 2.0 | 5.3 | 7,923.0 | 6.6 | 7,243.4 | – | 679.6 | 679.6 | – | Actual | – | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 30, 1999 (opens in a new tab) · document 2 (opens in a new tab) |
| FY 1999-00 | TABOR limit | 2.4 | 2.0 | 4.4 | 8,503.0 | 7.3 | 7,563.7 | – | 939.2 | 941.1 | – | Actual | – | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 30, 2000 (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2000-01 | TABOR limit | 2.9 | 2.2 | 5.1 | 8,877.1 | 4.4 | 7,948.6 | – | 928.6 | 927.2 | – | Actual | – | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 30, 2001 (opens in a new tab) · document 2 (opens in a new tab) · document 3 (opens in a new tab) · document 4 (opens in a new tab) |
| FY 2001-02 | TABOR limit | 4.0 | 6.0, not used | 4.0 | 7,752.2 | −12.7 | 8,126.2 | – | (365.7) | 0.0 | – | Actual | Population growth of 6.0% (census correction) was not used this year; it was banked as a growth dividend for later years. The revenue drop partly reflects new exemptions. | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 2002 (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2002-03 | TABOR limit | 4.7 | 2.2 | 6.9 | 7,712.5 | −0.5 | 8,296.8 | – | (584.3) | 0.0 | – | Actual | – | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 2003 (and Notes) (opens in a new tab) · document 2 (opens in a new tab) · document 3 (opens in a new tab) |
| FY 2003-04 | TABOR limit | 1.9 | 1.7 | 3.6 | 8,332.0 | 8.0 | 8,332.0 | – | 0.0 | 0.0 | – | Actual | Limit includes the growth dividend banked in FY 2001-02. | Schedule of Computations Required Under Article X, Section 20, State Controller's Office (CO Dept. of Personnel & Administration) as of June 2004 (with State Controller transmittal letter Dec 8, 2004) (opens in a new tab) · document 2 (opens in a new tab) · document 3 (opens in a new tab) · document 4 (opens in a new tab) |
| FY 2004-05 | TABOR limit | 1.1 | 1.1 | 2.2 | 8,483.4 | 1.8 | 8,309.5 | – | 170.8 | 43.0 | – | Actual | Limit includes the growth dividend banked in FY 2001-02. | OSA, Schedule of TABOR Revenue, September 2005 (Report 1742) (opens in a new tab) |
| FY 2005-06 | Referendum C time-out | 0.1 | 1.2 | 1.3 | 9,161.4 | 8.0 | 8,045.3 | – | 1,116.1 | 0.0 | 1,116.1 | Actual | – | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), February 2008 (Report 1927) (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2006-07 | Referendum C time-out | 2.1 | 1.4 | 3.5 | 9,641.9 | 5.2 | 8,333.8 | – | 1,308.0 | 0.0 | 1,308.0 | Actual | – | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), February 2008 (Report 1927) (opens in a new tab) |
| FY 2007-08 | Referendum C time-out | 3.6 | 2.0 | 5.6 | 9,998.6 | 3.7 | 8,829.1 | – | 1,169.4 | 0.0 | 1,169.4 | Actual | – | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), March 2010 (Report 2076) (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2008-09 | Referendum C time-out | 2.2 | 1.9 | 4.1 | 9,102.4 | −9.0 | 9,203.8 | – | (101.5) | 0.0 | 0.0 | Actual | Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $9,109,929,116. | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), March 2010 (Report 2076) (opens in a new tab) |
| FY 2009-10 | Referendum C time-out | 3.9 | 1.9 | 5.8 | 8,567.9 | −5.9 | 9,183.8 | – | (615.9) | 0.0 | 0.0 | Actual | Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $8,567,497,396. | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), Feb 2011 (Report 2076-10) (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2010-11 | Referendum C cap | −0.6 | 1.8 | 1.2 | 9,424.6 | 10.0 | 8,654.2 | 10,684.9 | (1,260.2) | 0.0 | 770.6 | Actual | – | OSA, Schedule of TABOR Revenue, Sept 2011 (Report 2054-11) (opens in a new tab) · document 2 (opens in a new tab) · document 3 (opens in a new tab) |
| FY 2011-12 | Referendum C cap | 1.9 | 0.1 | 2.0 | 10,273.2 | 9.0 | 8,799.8 | 10,871.4 | (598.2) | 0.0 | 1,473.4 | Actual | Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $10,269,103,335. | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), Feb 2013 (Report 2180-12) (opens in a new tab) |
| FY 2012-13 | Referendum C cap | 3.7 | 1.7 | 5.4 | 11,107.3 | 8.1 | 9,247.5 | 11,460.2 | (352.9) | 0.0 | 1,859.9 | Actual | Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $11,109,548,521. | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), Feb 2014 (Report 1301F-A) (opens in a new tab) |
| FY 2013-14 | Referendum C cap | 1.9 | 1.4 | 3.3 | 11,691.9 | 5.3 | 9,566.6 | 11,852.4 | (160.5) | 0.0 | 2,125.3 | Actual | Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $11,683,129,973. | OSA, Schedule of Computations Required Under Art. X Sec. 20 (TABOR), Feb 2015 (Report 1401F-A) (opens in a new tab) |
| FY 2014-15 | Referendum C cap | 2.8 | 1.5 | 4.3 | 12,530.8 | 7.2 | 9,976.9 | 12,361.0 | 169.7 | 169.7 | not printed | Actual | – | OSA, Schedule of TABOR Revenue FY2016, Oct 2016 (Report 1673P), OSC certification letter and schedule (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2015-16 | Referendum C cap | 2.8 | 1.6 | 4.4 | 12,824.4 | 2.3 | 10,427.6 | 12,946.5 | (122.1) | 0.0 | 2,396.8 | Actual | Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $12,904,019,740. | OSA, Schedule of TABOR Revenue FY2016 (Report 1673P) (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2016-17 | Referendum C cap | 1.2 | 1.9 | 3.1 | 12,891.9 | 0.5 | 10,761.7 | 13,327.8 | (435.9) | 0.0 | 2,130.3 | Actual | – | OSA, Schedule of TABOR Revenue FY2017, Oct 2017 (Report 1773P), OSC certification and Preliminary Schedule (opens in a new tab) |
| FY 2017-18 | Referendum C cap | 2.8 | 1.7 | 4.5 | 13,720.9 | 6.4 | 11,220.7 | 13,702.4 | 18.5 | 16.2 | not printed | Actual | The schedule certifies $16,202,687 over the cap for this year, and $37,529,475 to be refunded once $21,326,788 still owed from the FY 2014-15 surplus is added. This series counts each year’s own surplus once, so it carries $16,202,687. A later schedule restates the amount over the cap as $18,510,386; the over (under) column uses that restated figure. Revenue is the restated figure, the one that agrees with this row’s limit, cap and amount over or under. It was first certified as $13,718,573,027. | OSA, Schedule of TABOR Revenue FY2018, Oct 2018 (Report 1814P), OSC certification and Preliminary Schedule (opens in a new tab) · document 2 (opens in a new tab) |
| FY 2018-19 | Referendum C cap | 3.4 | 1.4 | 4.8 | 14,788.4 | 7.8 | 11,759.3 | 14,360.1 | 428.3 | 428.3 | not printed | Actual | The State Auditor’s report states $428,335,506 over the cap. The Controller’s letter adds $141,689 still owed from the FY 2014-15 surplus, for $428,477,195 in all. This series counts each year’s own surplus once. | OSA, Schedule of TABOR Revenue FY2019, Nov 2019 (Report 1914P), OSC certification letter and Preliminary Schedule (opens in a new tab) |
| FY 2019-20 | Referendum C cap | 2.7 | 1.4 | 4.1 | 14,866.3 | 0.5 | 12,241.5 | 14,948.8 | (82.5) | 0.0 | 2,624.8 | Actual | – | OSA, Schedule of TABOR Revenue, Fiscal Year 2020, Performance Audit (2014P), containing State Controller certification letter and Preliminary Schedule of Computations (opens in a new tab) |
| FY 2020-21 | Referendum C cap | 1.9 | 1.2 | 3.1 | 16,097.9 | 8.3 | 12,628.1 | 15,644.3 | 453.6 | 453.6 | 3,016.3 | Actual | – | OSA, Schedule of TABOR Revenue, Fiscal Year 2021 (2161P) (opens in a new tab) |
| FY 2021-22 | Referendum C cap | 1.9 | 0.3 | 2.2 | 19,747.0 | 22.7 | 12,929.8 | 16,012.4 | 3,734.6 | 3,734.6 | 3,082.6 | Actual | – | OSA, Schedule of TABOR Revenue, Fiscal Year 2022 (2252P) (opens in a new tab) |
| FY 2022-23 | Referendum C cap | 3.5 | 0.7 | 4.2 | 20,225.9 | 2.4 | 13,445.2 | 16,657.3 | 3,568.6 | 3,568.6 | 3,212.1 | Actual | – | OSA, Schedule of TABOR Revenue, Fiscal Year 2023 (2357P) (opens in a new tab) |
| FY 2023-24 | Referendum C cap | 8.0 | 0.5 | 8.5 | 19,444.7 | −3.9 | 14,588.1 | 18,073.2 | 1,371.5 | 1,371.5 | 3,485.1 | Actual | – | OSA, Schedule of TABOR Revenue, Fiscal Year 2024 (2457P) (opens in a new tab) |
| FY 2024-25 | Referendum C cap | 5.2 | 0.7 | 5.9 | 19,449.4 | 0.0 | 15,462.7 | 19,153.4 | 296.1 | 293.3 | 3,690.7 | Actual | – | OSA, Schedule of TABOR Revenue, Fiscal Year 2025 (2557P) (opens in a new tab) |
| FY 2025-26 | Referendum C cap | 2.3 | 1.3 | 3.6 | 19,835.4 | 2.0 | 16,187.7 | 20,011.3 | (175.9) | 0.0 | 3,647.7 | Preliminary | Preliminary: the State Auditor could not confirm the Controller figures. | OSA, Schedule of TABOR Revenue, Fiscal Year 2026 (2657P), incl. Sept 1 and Sept 8, 2026 Controller letters (opens in a new tab) · document 2 (opens in a new tab) |
How we figured this
- What is counted. Revenue subject to the TABOR limit (Colo. Const. art. X, sec. 20), which the State Controller measures as nonexempt state revenue. It leaves out federal funds, enterprises and revenue voters exempted, so it is not total state revenue or spending, and what counts as an enterprise changed over the years.
- Revenue change CALC is FY 2024-25 revenue ÷ FY 1992-93 revenue − 1: $19,449,446,624 ÷ $5,069,700,000 − 1.
- The compounded allowance CALC multiplies (1 + each year’s allowed growth rate) from FY 1993-94 through FY 2024-25, then subtracts 1. It is a yardstick, not the limit itself: the real limit also resets down after a revenue drop, and it moved with the growth dividend and Referendum C.
- Refunds owed CALC add the refund column over the years marked Actual. The refund owed for this year’s own surplus, as certified. Remainders of an earlier year’s surplus that a later schedule adds are not counted again. What was paid back through the refund mechanisms can differ from what was owed.
- Kept under Referendum C CALC adds the kept column over the years marked Actual. Revenue the state kept under Referendum C: all revenue above the TABOR limit in the time-out, and revenue between the TABOR limit and the cap after it. Blank where the schedule prints no figure.
- Over (under) the limit. The schedule’s own amount over (under) the limit in force: the TABOR limit through FY 2009-10, the Referendum C cap from FY 2010-11. In a few years it includes prior-year corrections the schedule prints, so it can differ from revenue minus the limit.
- Restated years. Where a later schedule restated a year, this page uses the figures that agree with each other in that year’s row, and the row’s note gives the first figure.
- FY 2025-26 is preliminary. The State Auditor could not confirm the Controller’s figures, so this year is left out of every total.
- Where the figures come from. State Controller schedules and State Auditor reports for most years. For FY 1992-93 to FY 1995-96 the Governor’s budget office, because no Controller schedule for those years survives online. Each row names its own documents.