Scotch Whisky of the last century
Before Single Malt Scotch Whisky became "fashionable" beginning of the 90ies, distillery managers or rather the master blenders were selecting their Single Malts almost as a hobby: from a variety of whisky casks they could choose at their discretion, which ones had what it takes for a special bottling.
These Single Malt bottlings were limited and very individual - and mostly bought by whisky connoisseurs, who at the time appreciated their Single Malt Whisky for drinking rather than collecting. Hence little is left of those Whiskies and the situation is further impaired by the closure of many distilleries in the meantime.
Demand for Whisky is growing
Since about 1995/2000 these "older" Single Malt bottlings have come into the focus of Whisky collectors.
In the meantime, the worldwide interest not only for Single Malt but Scotch Whisky in general has increased tremendously and existing distillery capacities can hardly satisfy the demand.
Growing quantities are used for blended Whisky, resulting in a reduced number of casks available for Single Malt bottlings and not least: less opportunity and leisure for a careful selection of such bottlings.
Changes in taste of Single Malts
Master blenders no longer have the same choice available to select only distinct casks for their Single Malt bottlings, which - over time - has led to a gradual variation of the taste of the respective Single Malt Whiskies.
Of course, also environmental changes as well as different types of wood used for the oak casks then and today, can have an influence on the maturing process and taste of the Whisky.
You can easily track these changes by making a blind tasting of e.g. three 12 yo bottlings of a certain distillery from different production eras (e.g. 80ies, 90ies and a current bottling).
Single Malt is getting scarce
So the quantities of those earlier ("older") Single Malt bottlings were limited and, to a large extent, have been consumed in the meantime by those first whisky lovers who enjoyed the exquisite character of the whiskies rather than putting them away in a collection.
Enter the new collectors and whisky fans from countries where Whisky has only recently been appreciated: India, China, Russia.
Prices have started to increase with the growing demand - and since those early era whiskies cannot be re-produced, it can be expected that the price trend for these Whisky rarities will continue and even accelerate.
The situation for "old" Whisky in the sense of longer maturing age is only slightly different.
