according to (article/no article) -- is there a rule to the madness?

Example #1:

In these two examples (the same news story) as you can see, there are articles in front of the noun phrases.

According to a new design specification from the Military-Industrial Commission in Moscow, a transport aircraft, dubbed PAK TA, will fly at supersonic speeds (up to 2,000 km/h) and will boast an impressively high payload of up to 200 tons. It will also have a range of at least 7,000 kilometers.

According to the source, the PAK TA project has been ongoing for several years now and will eventually supplant the currently operating air freighters. But such a global mission statement for national military transport aviation has never been voiced before.

Example #2:

However, in the following example, the article is not used at all, for some reason.

According to Bank of Russia forecast, the current monetary policy and low economic activity will be conducive to the slowing of annual consumer price growth to 9% over the year (March 2016 on March 2015) and to the target of 4% in 2017.

How would you explain that? Can you think of a rule that could help me make sense of things with regards to the usage of this expression?

Answer

The simple rule is: If you use a singular noun that is not a proper noun (i.e. the name of someone or something), it must be preceded by an article (a/the), a possessive pronoun (my/his/etc), or one of a small set of other adjectives (like "one").

This rule is unaffected by any other adjectives that may happen to be present. That is, for example, "dog" requires an article, like "the dog". If you say "big brown furry dog", it still requires an article: "THE big brown furry dog".

But if you used the dog's name, then there should not be an article. "Rover buried his bone", NOT "The Rover ..."

Don't get distracted by the words "according to". These have nothing to do with it. The rule would be the same regardless of what other words surround it.

So example 1 is correct. The noun is "specification". This is singular, and so requires an article.

Example 2 is incorrect. The noun is "forecast", which is singular, and so it should be "According to a Bank of Russia forecast ..."

I think the writer in example 2 was tripped up by the presence of the phrase "Bank of Russia". This is being used as an adjective to modify "forecast". What kind of forecast? A Bank of Russia forecast. But the writer may have seen the proper name here and thought that this meant there should not be an article.

It's also possible that an editor changed the sentence incorrectly. If the writer had left out the word "forecast" and used "Bank of Russia" as the noun, then there should be no article. "According to Bank of Russia, ..." If someone -- whether the original writer or someone else -- later said, "We really should specify that it's a forecast and not the current state", and so added the word forecast, they might have failed to realize that they now also needed to add an article.