At the latter stages of a bull market, enthusiasm can sometimes get the better of all of us. Investors always find ways to justify prices for companies at any stage in the cycle. To contrarians, the fact that the price of something has gone up tenfold doesn’t necessarily make it more attractive. However, momentum (as it is now called) is popularly touted as a sustainable investment strategy for the long term. Have the proponents of the ‘ever the greater fool’ theory had a re-brand? Within the world of investment trusts, ‘excessive optimism’ is more easily measured in terms of premiums to net asset value (NAV). This is particularly the case where the majority of a trust’s assets are themselves quoted. Of the 90 trusts (or investment companies) which currently stand on premiums, 55% have illiquid and/or unlisted assets representing greater than 50% of their portfolios. With these trusts, overenthusiasm is perhaps a little less easy to gauge – it is entirely possible that either valuations have moved on since the last official valuation, or that the board is being conservative in its valuations. Either way, each is likely to have its own story and a premium is not necessarily an indicator of excessive optimism. We list below the trusts which have greater than 50% of their assets in listed or publicly traded investments, yet trade at significant premiums. One of the common themes observable is that of strong relative performance over recent times. However, whether you are a contrarian or not (or a follower of momentum as a strategy), we believe that paying anything over a very modest premium is setting yourself up for a fall. Premiums are very rarely sustainable and tend to evaporate at inflection points, exacerbating a poor period of performance from a manager in absolute or relative terms. Indeed, the table below shows how quickly a premium can be eroded, with a corresponding effect on shareholder returns, irrespective of manager performance.