TI-84 ERR:STAT — What It Means & How to Fix It

What Does This Error Mean?

TI-84 ERR:STAT means there is a problem with the data in your statistical lists — either the lists have different lengths, all x-values are identical (making regression impossible), or you are running a regression with fewer than the minimum required data points. Check that both lists have the same number of entries and that the x-values are not all the same.

Affected Models

TI-84 Plus
TI-84 Plus Silver Edition
TI-84 Plus CE
TI-84 Plus CE-T
TI-83 Plus

Common Causes

Lists used for regression (e.g. L1 and L2) have different numbers of entries
All x-values in the list are identical — regression has no variation to fit
Only one data point entered — linear regression requires at least 2 points
Frequency list contains a zero or negative value
Attempting a two-variable statistic with only one list selected

How to Fix It

Check that both lists have the same length.

Press STAT → 1: Edit. Count the entries in L1 and L2 (use the arrow keys to scroll to the bottom of each list). The number in brackets at the top shows the current position. Both lists must have an equal number of entries for regression to work.
Check for duplicate x-values.

Scroll through L1 — if every x-value is the same number, a regression cannot be computed because there is no slope to calculate. Correct the list entries to ensure variation in x-values.
Ensure you have enough data points for the chosen regression.

Linear regression requires at least 2 data points. Quadratic regression requires at least 3 unique x-values. Exponential, power, and logarithmic regression require all y-values to be positive. Check the minimum requirements for the specific regression type.
Check the frequency list if using one.

If you specified a frequency list (Freq: L3 in the STAT CALC setup), open L3 and confirm every entry is a positive whole number. A frequency of 0 causes ERR:STAT.
Re-enter the data carefully.

Press STAT → 1: Edit, place the cursor on the L1 header, press CLEAR → ENTER to clear the list, then re-enter your data. Repeat for L2. After re-entering, run the regression again with STAT → CALC.

Frequently Asked Questions

Why does TI-84 ERR:STAT appear when my lists look correct?

A common hidden cause is an extra blank entry at the end of one list. Scroll all the way to the bottom of each list and check for a blank cursor position that isn't actually empty — delete any trailing blank entries.

Can I run regression on the TI-84 with data in columns other than L1 and L2?

Yes. When you open STAT → CALC and select a regression type, you can specify any list names in the Xlist and Ylist fields — not just L1 and L2. Press 2nd + the list number key to enter custom list names.