As we are concerned with long-term estimates, we have concentrated upon stocks at the longer end of the spectrum at around 15 years. Yes, the 2073 ILG is just over 50 years but it's still not been with us for that long and we have few conventional comparators. While not always the case over individual years, ILGs have not performed much better than conventionals. Between 1985 and 2021, over periods of 10 (15) years, the average ILG out-performance over conventionals was 0.08% (0.25%) per annum. 

Below, we present some statistical comparisons by duration, where the underlying assessment periods all start at the end of December. In particular, we are showing “long conventionals by duration”, “long ILGs by duration” and relative comparison performance charts for long gilts by start year over durations 10 years and 15 years.