Does string lengh and release angle affect a pendulums swing?

Questions:
1. Does the length of a pendulums string affect the rate of its swing?
2. Does the release angle of a pendulum affect the rate of its swing?

Procedure:
1. Using the constant weight of 1 washer and the constant release angle of 10 degrees, the length of string was altered (9", 12" and 21"). A stopwatch was used to time the swing rate.
2. Using the constant weight of 1 washer and the constant string length of 21", the release angle was altered ( 10, 40 and 90 degrees). A stopwatch was used to time the swing rate.
Figure 1. Image was borrowed from the internet. It depicts the experimental apparatus used.

Data:
Figure 2. Data from question 1.
Figure 3. Data from question 2.

Data Charts:Figure 4. Chart showing average time taken to complete one swing cycle at varied lengths.
Findings: Increased string length results in increased time taken to complete cycle.


Figure 5. Chart showing average time taken to complete one swing cycle at varied release angles.
Findings: Increased release angle did not necessarily result in an increased time needed to complete one swing cycle. The mean time showed no correlation between angle and swing time.

Conclusions:
- The longer the string the longer it takes to complete one swing cycle.
- The release angle has no effect on swing time.
- Stop watches and relatively short pendulums are not adequate materials to do this test properly

Remaining Questions:
- What if significantly longer strings were used? Would the release angle data be cleaner?