Looking at the post, it's unclear to me what your goal is.
You're acquiring data at 1kHz. You want to log at 1Hz.
Are you wanting to log 1000 data points every 1 second? Or, are you wanting to log a single value every 1 second?
If you want to do the first, decimation won't work. But, having a second loop can handle that for you. If you want to do the second, Bob's VI should work for you with small changes. You can pull the date string from the first entry to get a time and feed the numbers into a mean function. Or, you could just take the first and be content.
