I encountered the following in a 1958 book on investing:
How has the market price of these shares responded to all this? Has the price-earning ratio continued to advance as, twenty-two months ago, I indicated appeared probable?
The last part made bold is the difficulty for me.
So I can ignore the middle sentence "twenty-two months ago", and focus on
Has the price-earning ratio continued to advance as I indicated appeared probable?
In this question, it seems to me that some words are missing. I can guess the meaning is
Has the price-earning ratio continued to advance as I indicated (that) (it) appeared (to be) probable?
But it looks like there are several grammatical rules involved here, that the author used to omit these parts, and I can't understand the interplay of these rules.
Could you help explain the rules which allowed the author to write this question in such form?
I know it involves omitting "to be" after linking verbs such as "appear," and that you can omit "that" before complements, but why "it" can be omitted, whether after "as" or in general? or otherwise is there some other grammatical rule that I'm missing here?