RBNZ says material monetary policy surprises are relatively rare.

The Reserve Bank of New Zealand has published a new 'Analytical Note' that seeks to assess monetary policy surprises and how they impact on financial market instruments.

Material monetary policy surprises are defined as instances where market pricing for the OCR immediately prior to an announcement is more than 5 basis points different from the announced rate. And they RBNZ says such occurrences "are relatively rare."

Since 2006, fewer than 1 in 5 OCR announcements resulted in a material monetary policy surprise (see red dots in Figure 1, below).

Here is the link to the Note for much more.