Returns the age-interpolated median of the Dutch references (van Buuren 2014).
The working range is 0-3 years. This function should
be called when the `key = "dutch"`

.

## Arguments

- t
Decimal age, numeric vector

## Value

A vector of length `length(t)`

with the median of the Dutch references.

## Note

Internal function. Called by `dscore()`

## Examples

```
dscore:::count_mu_dutch(0:2)
#> [1] 4.88220 48.90290 63.83718
```