I am plotting 20+ timeseries with various scales from a `DataFrame`

using `Plots.jl`

, separated into subplots because the original plot is too crowded. Everything works nicely, but I would like a separate legend (with only the plotted series) for each subplot. Self-contained **toy example**:

```
using DataFrames
using Plots
using StatPlots
data = let years=[], spelltypes=[], values=[]
for year in 1980:2000
for spelltype in 1:30
push!(values, spelltype+(rand()-0.5)/10)
push!(years, year)
push!(spelltypes, spelltype)
end
end
DataFrame(year=years, spelltype=spelltypes, value=values)
end
pick(data, range) = data[[spelltype â range for spelltype in data[:spelltype]],:]
subplot(data, range) = plot(pick(data, range), :year, :value, group=:spelltype)
p1 = subplot(data, 1:10)
p2 = subplot(data, 11:20)
p3 = subplot(data, 21:30)
plot(p1, p2, p3) # would like separate legend for each subplot
```