Perfect Tense

The perfect tenses generally indicate action completed before another specific time or action.  The present perfect tense also indicates action begun in the past and continued into he present.  The perfect tenses consist of a form of have plus the verb's past participle.

Present perfect

The dancer has performed here only once. [The action is completed at the time of the statement.]

Present perfect

Critics have written about the performance ever since. [The action began in the past and continues now.]

Past perfect

The dancer had trained  in Asia before his performance. [The action was completed before another past action.]

Future perfect

He will have performed here again by next month. [The action begins now or in the future and will be completed by a specified time in the future.]

With the present perfect tense, the words since and for are followed by different information. 

After since, give a specific point in time: 

The United States has been a member of the United Nations since 1945. 

After for, give a span of time:

The United States has been a member of the United Nationsfor over half a century.

Subjects and Verbs

Readers feel they understand what you wrote when you do 2 things:
1.  You use subjects to name your central character.
2.  You express their most important action as a verb.

Federalist --> argued
They --> believe
Little Red Riding Hood --> walked

NOT
The argument --> was based

INSTEAD
They --> argued

Don't make your most important ACTION a Noun.  Use them as VERBS!

Confusing sentence

Our lack of data prevented evaluation of state actions in targeting fund to areas in need of assistance.
What?  .

Fix with -->
We lacked data.  We could not evaluate.that  the state had targeted funds to areas that needed assistance.

Try to keep the same character as your subject....in this example "We" is the consistent subject.

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