# Yield curve: Turn of year effect jump calculation

I'm trying to get the values for the turn of year jumps that can be found at section 4.8 of

Everything You Always Wanted to Know About Multiple Interest Rate Curve Bootstrapping But Were Afraid To Ask

and I don't see how the 8.5 bps for the eonia at 2014 are calculated.

In this section it says:

...we are allowed to estimate the coefficient using instruments with a given underlying rate tenor (e.g. those on Euribor3M used for C3M ), and to apply it to any other curve Cx taking into account the proper weights...

Does this mean is it taking the value from another tenor rates?

In this section also says:

The Con yield curve displays both the 2013 (10.2 bps) ON and the 2014 (8.5 bps) turn of year jumps. The C1m yield curve displays the 2014 turn 1M of year jump between 1st Dec. 2013 (+1.8 bps) and 2nd Jan. 2014 (−1.6 bps) with size roughly equal to 1/20 of the ON jumps

This makes me more confused as it talks about a size for 1M jump of roughly 1/20 of ON jump and:

• I don't see where the 1/20 applies (it later talks about jump for 3M is 1/3 of 1M jump which is 0.6bps and 0.5bps and makes sense to me)
• As it says is roughly equal makes me think this value has been calculated in a different way and then compared to what should be