There are many different views, for lots of good reasons, as to what defines a trade period. But let’s try this:
Day trading, as the word suggests, is a trade that is entered and exited within the same day. Mostly this will be technical trading, but could be news or event based.
Short-term trading is again primarily technical; but could include fundamental, news and event based criteria. Usually one day out to several months.
Medium term could be 9 months (as defined by Peter Lynch as the period beyond which fundamental information provides all the influence) out to several years.
Between medium term and long-term we see a gap. A sort of no man’s (or women’s) land.
A large correction, substantial pull-back or crash (call it what you will) happens between 7 and 15 years. Historically not before 7 years, but could be more than 15 years.
So, lets take 15 years as a guide. For our ‘long term’ investments to survive, to grow, they may have to outlast a couple of crashes. That takes the longer term to 30 years, or thereabouts, depending on the date of purchase of the investment relative to a previous crash.
It makes sense therefore that investment money that is needed for a pension ought not to be invested over the medium term some 7 to 15 years from a previous crash.
2008 was our last crash, so between 2015 and 2023, or until the next one, it might be prudent to only invest short-term or longer term.
And, we would say long-term only with excellent value equities probably purchased prior to 2015.