Some more exchange traded funds (ETFs) are closing their doors.

This time, it’s five Treasury bond ETFs that launched last June:

• Ameristock/Ryan 1 Year Treasury (GKA)
• Ameristock/Ryan 2 Year Treasury (GKB)
• Ameristock/Ryan 5 Year Treasury (GKC)
• Ameristock/Ryan 10 Year Treasury (GKD)
• Ameristock/Ryan 20 Year Treasury (GKE)

The ETFs were based on fundamentally weighted indexes created by Ron Ryan of Ryan ALM. Ryan told us earlier this month that he believes fundamentally weighted bond indexes are the solution to problems with equal-weight bond indexes. In total, the five funds had $13 million in assets, says Murray Coleman for Index Universe.

The last day of trading will be June 10, and from June 11 to June 19, they will be liquidated.

This is the second major ETF closing. The first came in February, when Claymore shut the door on 11 funds.

We predicted that this wouldn’t be the first round of fund closings, and there will likely be more down the road. It’s a natural thing in any industry, not just ETFs: some products take off, others aren’t always going to be accepted by the marketplace.