Leftmost digit of Fibonacci sequence

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So, on another math forum, someone posted a question about the leftmost digit of a randomly chosen Fibonacci number. It likely follows Benford's Law for the distribution of the leftmost digit.

I know the rightmost digit is cyclic with a cycle of 60, so I wanted to check if there was any kind of repetition for the leftmost digit. It seems that $F(n+67)$ and $F(n)$ have the same first digit a surprisingly high percentage of the time (my calculations put it at around 97% for the first 1000 Fibonacci numbers). I tried to see if this was understood at all, or just another mystery of the Fibonacci numbers, but after a few hours of searching, I did not come across anything.

You can see it in action with this graph:

http://www.wolframalpha.com/input/?i=FLOOR%5BFibonacci%5Bn%2B67%5D%2F10%5E(FLOOR(Log%5BFibonacci%5Bn%2B67%5D%5D%2FLog%5B10%5D))%5D-FLOOR%5BFibonacci%5Bn%5D%2F10%5E(FLOOR(Log%5BFibonacci%5Bn%5D%5D%2FLog%5B10%5D))%5D

Anyway, back to my question. Does anyone know of any research related to this?

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Community wiki answer so the question can be marked as answered:

The question has been answered in the comments. The observed regularity is due to the proximity of $\phi^{67}$ to a power of $10$.