# Version 0.8.1 (July 22, 2012)

This release includes a few new features, performance enhancements, and over 30 bug fixes from 0.8.0. New features include notably NA friendly string processing functionality and a series of new plot types and options.

## New features

> - Add vectorized string processing methods accessible via Series.str (GH620)

> - Add option to disable adjustment in EWMA (GH1584)

> - Radviz plot (GH1566)

> - Parallel coordinates plot

> - Bootstrap plot

> - Per column styles and secondary y-axis plotting (GH1559)

> - New datetime converters millisecond plotting (GH1599)

> - Add option to disable “sparse” display of hierarchical indexes (GH1538)

> - Series/DataFrame’s `set_index` method can append levels to an existing Index/MultiIndex (GH1569, GH1577)

## Performance improvements

> - Improved implementation of rolling min and max (thanks to Bottleneck !)

> - Add accelerated `'median'` GroupBy option (GH1358)

> - Significantly improve the performance of parsing ISO8601-format date strings with `DatetimeIndex` or `to_datetime` (GH1571)

> - Improve the performance of GroupBy on single-key aggregations and use with Categorical types

> - Significant datetime parsing performance improvements

## Contributors

For contributors, please see /usr/share/doc/contributors_list.txt or https://github.com/pandas-dev/pandas/graphs/contributors