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Below I have reproduced a table from a 2011 Pew study on Christian Movements and Denominations which used data from the Gordon-Conwell Theological Seminary Center for the Study of Global Christianity.
+-----------------------------------------------------+-------------------------------+
| Denominational family | Percentage of all Protestants |
+-----------------------------------------------------+-------------------------------+
| Historically pentecostal denomination | 10.8% |
| Anglican | 10.6% |
| Lutheran | 9.7% |
| Baptist | 9.0% |
| United churches (unions of different denominations) | 7.2% |
| Presbyterian or Reformed | 7.0% |
| Methodist | 3.4% |
| Adventist | 2.7% |
| Congregationalist | 0.5% |
| Brethren | 0.5% |
| Salvation Army | 0.3% |
| Moravian | 0.1% |
| Other (independent, nondenominational and others) | 38.2% |
+-----------------------------------------------------+-------------------------------+
I would classify each of these denominations as one of the following:
Lutheran: influenced by the theology of Martin Luther, the father of the Reformation. Over time, Lutheranism has evolved on the issue of soteriology, but it remains distinct from Calvinism and Arminianism while emphasizing the principle of sola fide (salvation by faith alone), which is common to all Protestant denominations. Above, Lutherans (obviously) and Moravians would qualify as Lutheran.
Arminian: influenced by the theology of Jacob Arminius, whose followers drafted the Five Articles of Remonstrance in opposition to what they perceived as errors in Reformed soteriology. Arminian denominations also have a historical connection to the teachings of John Wesley, an avowed Arminian. Above, these denominations include Pentecostalism, Methodism, Adventism, and the Salvation Army.
Reformed: influenced by the theology of John Calvin, and united in adherence to the five points of Calvinism, which are summarized in the acronym TULIP and based on articles drafted at the Synod of Dort in response to the Five Articles of Remonstrance. Above, I would only classify "Presbyterian or Reformed" as Reformed.
Anabaptist: rooted in the Radical Reformation, which occurred at the same time as the Reformation but took a different tack. Early Anabaptists have been called proto-Arminians, and among modern Anabaptists you'll be hard-pressed to find any Calvinists; you'll either find people close to Arminianism, or adherents of open theism, which is even further from Calvinist doctrine. Above, I would only classify "Brethren" churches as Anabaptist.
Mixed: many denominations have no stance on these soteriological doctrines. While individuals (or individual congregations, or even the odd denominational institution) may have their own convictions, the Anglican, Baptist, United, and Congregationalist families as a whole do not take a position on Calvinism or Arminianism.
Another complication is that individuals may or may not adhere to the official or traditional teachings of their denomination. For example, though Pentecostalism is rooted in the Wesleyan/Holiness movement, as of 2010 31% of American Pentecostal/charismatic pastors described themselves as reformed according to Barna Research.
But below, I have used the original Pew table to demonstrate what percentage of world Protestants belong to denominational families that are either Lutheran, Reformed, Anabaptist, or mixed.
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| Denominational family's soteriological bent | Percentage of all Protestants |
+---------------------------------------------+-------------------------------+
| Mixed | 65.5% |
| Arminian | 17.2% |
| Lutheran | 9.8% |
| Reformed | 7.0% |
| Anabaptist | 0.5% |
+---------------------------------------------+-------------------------------+
I haven't been able to find good statistics on how many Protestants in the "mixed" category identify as Calvinists, how many identify as Arminians, and how many would identify as some kind of "other." Affable Geek has a couple posts on this site explaining how a lot of Baptists let Calvinist and Arminian principles operate side-by-side.