question about the participle phrase 'rising to'

[littleridinghood]

I am a little confused about what the participle phrase 'rising to' modifies in the following three setences. Does it modify the subject of the main clause or the number in the main clause?
I may have been taught in high shcool that the participle phrase can only modify the subject of a main clause, or the word right in front of a participle phrase, but these two rules seem to be inappropriate in the cases listed below:

1 Coal was used to produce 50 of the total 100 units of electricity in Australia in 1980, rising to 130 out of 170 units in 2000.

2 Washing machines were the fourth most common item, with 66% of households owning one in 1972, rising to 80% of households in 1983.

3 These places are home to almost 3 billion people, rising to 5 billion by mid-century.

 

[entangledbank]

It's hard to say it modifies anything. It's attached at the end, as would be a preposition phrase expressing the same thing:

These places are home to almost 3 billion people, with the number rising to 5 billion by mid-century.

But you can't actually attach the 'rising' clause directly to an antecedent in the original sentences, nor even add mention of the word 'number' before the first number, to make the attachment easier. The antecedent is obviously, in some sense, the numbers 50 out of 100, 66%, and 3 billion, but it is not a tight grammatical link.

 

[PaulQ]

1 Coal was used to produce 50 of the total 100 units of electricity in Australia in 1980, and this (50 of the total 100 units of electricity in Australia in 1980) rose to 130 out of 170 units in 2000.

2 Washing machines were the fourth most common item, with 66% of households owning one in 1972, and this (66% of households owning one in 1972) rose to 80% of households in 1983.

3 These places are home to almost 3 billion people, and this (almost 3 billion people) rose to 5 billion by mid-century.

"Rising to ..." = "this rose to" and refers to the similar phrase in the preceding clause. "This" is a pronoun.

Crosspost.