Cyclical stocks are ones that are influenced by economic and business cycles.
When the economy is doing well and consumers/businesses are spending money, cyclical companies tend to do well.
When
economy starts to slow down and consumer spending shrinks, cyclicals companies suffer too.
e.g. steel is an industry whose fortunes are closely related to global economic growth.
Individual sectors have their own cycles too, which are generally based on capacities and demand. When demand is more than the capacity, the sector tends to do well. Prices remain firm and almost all output is consumed. When there is over-capacity in the sector, both prices and capacity utilization falls.
e.g. sugar has been following its own cycle since the last few years.
sugar industry was suffering from over-supply when the world economy was booming and now when the global economy is down, there is a shortage of sugar and prices are sky-high.
Individual companies also have their own internal cycles which depend on
-how fast they build inventories and get rid of it.
-capacity utilization etc.
Some sectors are usually resilient to external cycles.
-essentials like pharma aren't influenced by economic cycles.
-sectors where demand far exceeds the supply, are not influenced by economic cycles.
e.g. education sector. top private colleges are charging heavy fees....even in a recession...

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-sectors closely regulated by government are also not influenced by economic cycles.
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Neither economic, sector-specific or company-specific cycle have a fixed time-period.
only type of cycle that has a fixed period is
seasonality.
e.g. fireworks industry in India always has its peak during Diwali.
however, even the fireworks industry in influenced by overall economic conditions in the county.
people spend less during Diwali in recessionary times.
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besides the cycles that influence companies, stocks themselves are influenced by cycles in
money supply and interest rates.
it would have been easy to anticipate stock price movements if there was just a single cycle influencing them.
however that is not the case.
companies (and stocks) are influenced by multiple cycles at the same time and most of these cycles don't have any fixed time-periods.
according to many analysts, even human behaviour and sentiments are cyclical in nature and there are indicators built to measure them too...

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