"decreasing support" is correct and usable in written English.
It can be used when referring to a decline in the availability or amount of help or resources given to someone or something. For example: "The organization saw a steady decrease in support from government and private entities over the past decade."
Successive polls in the Muslim world have shown decreasing support for radical Islam and Bin Laden since around 2005.
Further, behavioral invisibility of information is exacerbated by the decreasing support for complex search operators in open web search engines.
The UK's solar industry has been in turmoil in recent months, with hundreds of job losses already under way and more threatened as a result of the government's decreasing support for the technology.
From that time forward, however, and despite decreasing support from English investors, the health and the economic position of the colonists improved.
Now the time has come for new leadership to step into the director's role with fresh ideas and energy to carry the DLC yet further toward international impact in this critical time of decreasing support for the sciences and increasing threats to global biodiversity and the natural environment.
Decreasing support for stricter gun laws.
This is largely explained by decreased support from states.
Their strategy of mobilising the religious right and risking decreased support among moderates failed.
Such actions decreased support for the insurgency, which had always been limited.
Adding $2 to an electricity bill decreased support for an RPS policy by about 6percentt, while a $10 increase decreased support by fully 13percentt.
Positive stories about appointing specialists instead of generalists to senior civil service positions led to decreased support for appointing specialists.
