# How to compute interest rate futures spread ratio?

I am confused on how to compute the spread ratio.

For example, this is example I came across with my broker -

Consider 2 contracts Bobl and Euribor.

The DV01 of Bobl i 44.8 and Euribor is 25. To equalize DV01, we need 44.8/25=1.792 contracts of Euribor for every 1 contract of Bobl. However, tick sizes are different. 1 Bobl Tick is 10 Euros and similar Euribor tick is 25. So the ratio will be for 1 Bobl we need 1.79*(25/10) = 4.475 contracts of Euribor.

I understand DV01 sensitivity to compute the hedge ratio. However, I don't understand how is he using tick sizes. If he related tick sizes to basis points, it would have made more sense to me.

Does someone understand this?

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