Tense

[APARIDA]

Hi,

Could you please explain why the following sentence is correct? I found a similar sentence in OG as a correct choice and hence this question.

Note: I came up with the following sentence and it's not a CUT/PASTE from OG. I just want to discuss the concept.

The results of federal aid to company X are evident in company's stock prices, which have increased 10% during the first 4 months of this year after falling over the last 5 years.

In the above example, it is evident that the period "first 4 months of this year" is in past otherwise the results (10% increase) would not have been out. Hence the verb tense should be in past. What is the reasoning behind using the present tense in the above sentence? Is it because the "10% increase" started in past and may be still in effect? What if the original sentence (choice A) has the verb tense in past? In such cases, can we change the verb tense to present which might change the meaning of the sentence?

Also, OG states that in such sentences the verb tense has to distinguish between the times at which the indicators occurred. Why is it so important when we have "after" in the sentence? I read it in one of the MGMAT forums that when the sequence of events is clear from other parts of a sentence, verbs may not have to indicate the sequence. Please confirm my understanding.

If my understanding is correct, then following is the correct representation (grammatically) of the above sentence

The results of federal aid to company X are evident in company's stock prices, which increased 10% during the first 4 months of this year after they fell over the last 5 years.

I know above sentence sounds awkward as "after they fell over the last 5 years" does not sound quite right. I think the tense should be progressive. Or may be we can change the last part of the sentence to "after they fell last quarter".

Please clarify.

Many thanks for your continuous help.

[kramacha1979]

I think the only reason the original sentence has progressive is to highlight that 'falling' took place through out the entire 5 year period.

It was a continuous thing..

yeah they fell over the last 5 years sounds awkward....
Note you might be introducing they w/o a clear antecedent ..

[JonathanSchneider]

First of all, we don't have the present tense, we have the present perfect: "have increased." The present perfect is the tense that shows something that started in the past and continues into the present, or that happened in the past but is still true/relevant in the present. In this case, we want the present perfect because the first part of the sentence indicates that the results "ARE present in ... prices." Thus, the prices are in the present. Although the changes may have started in the past, we need to show that they "have risen" up to their current price.

As for "after," this word shows the time relationship between "have risen" and "falling," NOT between "have risen" and "are present." Moreover, "falling" is not a verb, so it has no tense.