I wonder whether the use of the word "underpinned" is correct in the following sentence and if there is a synonym for this word that fits in the sentence (when I try to look for synonyms on thesaurus I do not find a right synonym):
Since some [people] have underpinned demand for these [items], the price of these [items] has to [decline/increase] to restore equilibrium in the [some] market.
Another example, taken from an academic paper, is the following:
If there are preferred habitats then the demand for these preferred securities is underpinned, giving scope for quantities to matter in their price determination.
To be clear, I talk about people (investors) who have a preference for a particular security. In this way, their demand is "underpinned". However, my supervisor found this word a bit odd. A synonym or rewriting the sentence could therefore also be an option.