whence the deliberate decision to include XXXX in the budget..
OR
They are determined to take the figure to YYYY. It is therefore no accident/not by chance that plans include two new XXXXX

This is my "standard" translation for the word that works pretty much unfailingly in contexts of action plans, human will, etc. Of course in a budget context "determined" might be taken to mean "a budget of a pre-determined amount" (what else IS a budget, though?) rather than "resolute", "firm", "staunch",, "a budget that is determined to achieve certain objectives", but if there is likely to be any doubt about the meaning, in context, there are ways of getting round that, like "a staunchly/firmly/strongly determined budget".



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Note added at 32 mins (2010-05-14 12:41:46 GMT)
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As I thought, this word has come up before, about four times at least, including this:
http://www.proz.com/kudoz/french_to_english/business_commerc...

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Note added at 37 mins (2010-05-14 12:45:53 GMT)
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Of course volontariste can also be a euphemism for "hopelessly optimistic, really, and most unlikely to achieve the desired results, much as we wish it would, but we'll put up a good show while we can, chaps, keep on fighting, and go down the gurgler with our boots on".

"Volontariste" often means "proactive", but I have a feeling that the equivalent word in this context could be aggressive. Budgets are often described as being aggressive in EN; in FR, of course, it would be nonsensical to talk of a "budget aggressif", so "volontariste" could be another way of getting at the same thing.

"Ambitious" could be another option, though is not quite getting at the same thing.

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Note added at 42 mins (2010-05-14 12:51:09 GMT)
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As I said above, "ambitious" could be an option – though, since Google has over 22k hits for "budget ambitieux", I tend to think they would have said that if they meant it.

...

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Note added at 20 hrs (2010-05-15 08:14:39 GMT)
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The word "volontarisme", although coined about 40 years ago (in the late sixties, I believe) is still a neologism because it retains its full meaning only within particular french intellectual debates, among and around marxist thought...Those who believed that sheer will could transcend "objective" "deterministic" factors were (pejoratively in most cases) labeled "volontaristes"... In the anglo-saxon context, particularly the American one, "volontarisme" looses all its "meaningful" power since there is (almost) no debate as to "how to make history". Shared, undiscussed wisdom is that human will is indeed a strong acting factor but only in the making of the economy... "Entrepreneurship" is at the heart of that...

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Note added at 1 day34 mins (2010-05-15 12:43:07 GMT)
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An error to be corrected: "volontarism", say both Quillet and Robert, was "invented" not in the 60s but in 1909. But It's safe to suppose that its use was restricted to philosophical circles. Sorry.