By analysing past share price data it is possible to calculate the historic average returns on all days, weeks and months of the year. For example, since 1984 the LSE has traded 23 times on 8 January with an average return (of the FTSE 100) of -0.03%. Similarly, over the same period the FTSE 100 has had an average return of -0.49% in the second week of the year.
The Almanac has conducted such analysis of the historic behaviour for four stock indices:
The analysis produces three numbers (the Sinclair Numbers) for each day, week and month of the year: