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How Does the Gallup Investor Optimism Index Work?

How Does the Gallup Investor Optimism Index Work?

What is the Gallup Investor Optimism Index?

The Gallup Investor Optimism Index is a broad measure of U.S. investors' outlook on their finances and the economy. The index measures investors' views on their future income and investment performance, as well as their expectations for economic growth, unemployment, stocks and inflation. The Gallup Investor Optimism Index is an enhanced version of Gallup's Index of Investor Optimism, which provides historical trends dating back to 1996.

Gallup analyzes results from the index each quarter based on all investors, which includes retired and nonretired investors. Approximately seven in 10 investors surveyed are not retired, and approximately three in 10 are retired.

For this survey, Gallup defines the American investor as a male or female adult in a household with total investments of $10,000 or more. These investments can be in stocks, bonds, or mutual funds in an investment account or in a self-directed IRA or 401(k) retirement account. About two in five American households that Gallup surveys for the index have at least $10,000 in investments.

How are interviews for the Gallup Investor Optimism Index conducted?

Since 2018, Gallup has conducted the Gallup Investor Optimism Index survey by web using the Gallup Panel.

The Gallup Panel is a probability-based longitudinal panel of U.S. adults, recruited from random-digit-dial Gallup telephone surveys that cover landline and cellphones. Gallup also uses address-based sampling methods to recruit Panel members. The Gallup Panel is not an opt-in panel. Each Gallup Panel sample is weighted to be demographically representative of the U.S. adult population, using the most recent Current Population Survey figures.

From 2011 to 2017, investors were surveyed by phone, using nationally representative samples of U.S. adults aged 18 and older living in all 50 states and the District of Columbia. Gallup sampled landline and cellphone numbers using random-digit-dial methods, and landline respondents were selected at random within each household based on which member had the next birthday. Interviews were conducted in Spanish for primarily-Spanish speaking respondents.

How do the interviews conducted by Gallup Panel compare with the historical trends conducted by RDD telephone?

In anticipation of there being mode differences in the way respondents answered questions by telephone vs. online, Gallup conducted large-sample parallel telephone and web studies of the Investor survey in Q1 of 2018. Gallup used the observed differences between the two surveys to compute mode adjustment factors for the 2011-2017 telephone trends, bringing them into line with the 2018-Q1 web-based results.

For index trends prior to 2011, a mode adjustment was done by means of regression analysis and applied to the overall Investor Optimism Index, as well as to the Personal Index and Economic Index.

The following graph displays the impact of the mode adjustments on the overall Gallup Investor Optimism Index, from 1996 to 2017. The mode adjustments lower the index score for the overall index by an average 22 points, within a range of 17 to 29 points.

Line graph. The two different modes of the Gallup Investor Optimism Index, from 1997 to 2018. The two modes are the original unadjusted RDD telephone trend and a revised mode-adjusted trend. The mode adjustment generally lowered the index over the course of the trend.


How many people are interviewed as part of the Gallup Investor Optimism Index?

Gallup interviews approximately 1,000 investors each quarter for the Gallup Investor Optimism Index.

How often are the Gallup Investor Optimism Index interviews conducted?

Gallup has been interviewing investors quarterly for the Gallup Investor Optimism Index since 2011.

Where can I find results from the Gallup Investor Optimism Index and learn more about the survey?

Gallup reports in-depth findings from the Gallup Investor Optimism Index on A complete listing of Gallup articles since 2012 can be found on the Gallup Investor Optimism Index topic page.

Sign up for Gallup News alerts to get these articles as soon as they are published. For additional information about how this survey is conducted, please contact

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