This article concerns the daily returns for the FTSE 100 Index from 1984.

## Average daily returns

The following table shows the *average return* since 1984 of the FTSE 100 Index for each day of the year. For example, over the last 31 years the average daily return for the FTSE 100 Index on 2 January has been 0.37%.

In the table, *positive* average daily returns are coloured **green**, while *negative* average returns are coloured **red**. Daily returns are highlighted dark green (red) for *large* positive (negative) returns. (See below for the definition of large.)

*Observations*:

- The periods of greatest relative strength for daily returns (i.e. clusters of dark green cells in the table) would appear to be the first couple of days of each month, and the second part of December.
- Conversely, the period of greatest relative weakness for daily returns (i.e. clusters of dark red cells in the table) would appear to be the five-days of 20th to 24th of each month (except December).
- The day of the month with the greatest number of large positive returns is the 1st; while the greatest number of large negative returns is the 22nd.

## Positive daily returns

The following chart is similar to the above, except this shows the *proportion of positive returns* for each day of the year. For example, since 1984 56% of the FTSE 100 Index returns on 2 January have been positive.

## Definition of large

Values are highlighted as *large* if they are more than 1 standard deviation from the average. For example, for the daily returns in the first chart the average daily return (for all days) is 0.03% and the standard deviation 0.24, so values are highlighted if they are above 0.27% (0.03 + 0.24) or below -0.21% (0.03 – 0.24).

Other daily return heatmaps.