changing value of value field changes chart width

I'm using v0.9.2 and dynamically building the datasets and charts within the JS code.

Within a loop, this code produces an acceptable chart:

```
var attr = {
"attributes": {
"age": i,
"percent": currentCountryData["SD_mean_" + i]
}
}
```


But when I change that decimal value to a percent,

`"percent": currentCountryData["SD_mean_" + i] * 100`

It creates all this whitespace to the left of the Y-axis. Any idea why?