This is because April has been the best month for returns. Since 1966 the All-Share index has given an average total return in the month of 2.9 per cent. That compares to an average for all months of 1.1 per cent. If variations in returns were due to chance, there would be only a 0.6 per cent probability of us seeing such a big difference between April and the other months.
In particular, losses are rare in April. In the past 50 years, there have been only nine losses in April. That's 18 per cent, which is less than half the frequency of losses in other months; there have been 212 losses in these 552 months, a frequency of 38.4 per cent. And April has seen only two losses of 5 per cent or more. Such losses are three times as common in the other eleven months of the year.