Possibly attempt object -> float64 coercion in to_sparse
something like

`array([82.87, 82.1, 84.25, 84.53, 85.9, 85.9, 86.95, 88.13, 89.49, 89.76,
       90.76, 88.99, 89.42, 89.0, 89.49, 88.95, 89.09, 88.65, 88.52, 88.98], dtype=object)`

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