Certain interest-related dividends. There is no 30% tax on interest-related dividends from sources within the United States that you receive from a mutual fund or other regulated investment company (RIC). The mutual fund will designate in writing which dividends are interest-related dividends. Certain short-term capital gain dividends. There may not be any 30% tax on certain short-term capital gain dividends from sources within the United States that you receive from a mutual fund or other RIC. The mutual fund will designate in writing which dividends are short-term capital gain dividends. This tax relief will not apply to you if you are present in the United States for 183 days or more during your tax year.
在Fidelity那张表里，
Fidelity® Government Money Market Fund可refund 93.67%，Fidelity® Treasury Money Market Fund 可refund 96%，这样下来估计税率大概只有原来的~1/20。
问题是withholding的影响有多大？假设没有treaty按30% tax rate和withhold rate算。另外假设一整年每月distribution都是0.004，dividend reinvest，可refund 96%。那么一年下来
pre tax total = (1+0.004)^12 = 1.049070208
tax withheld, before refund = (1+0.004*(1-0.3))^12 = (1+0.0028)^12 = 1.0341223
refund = 0.96 * sum_{i=0^11} 0.3 * 0.004 * (1+0.0028)^i = 0.96 * 0.3 * 0.004 * ((1+0.0028)^12-1)/0.0028 = 0.01403888914
after tax total = 1.04816118914
tax rate = 1 - (0.04816118914/0.049070208) ≈ 1.85%
比起直接30%*(1-0.96)=1.2%，可见withholding影响有，但还是税率还是很低。
哦，抱歉看漏了。IRS Publication 519 p16里dividend其实说了三种，第一种U.S. source dividends you receive from a foreign corporation对坛里大多数人应该不适用。第二种interest-related dividends我感觉确实不用交税，但是第三种有This tax relief will not apply to you if you are present in the United States for 183 days or more during your tax year.，对坛里大多数人来说只适用于来美第一年。Fidelity表里把第二种和第三种混到一起去了，所以我刚找了一下我去年的1099来看具体比例。
我去年在Fidelity上买了非常少的SPAXX和SPRXX，1099-DIV line 12 Exempt Interest Dividends是0，而且有一条备注说Short-term capital gain distributions reported on monthly/quarterly account statements are included in 1a Total Ordinary Dividends on Form 1099-DIV.，因此我去年在美国超过183天就肯定没税可减了。我去年在Schwab上买了更多的SWVXX，1099-DIV line 12 Exempt-Interest Dividends和line 2a Total Capital Gain Distributions都是0。难道只有Fidelity这个表上的基金有interest-related dividends和short-term capital gain dividends？
1099-DIV line 12 Exempt Interest Dividends，Fidelity另有一张表：2022 Tax-Exempt Income from Fidelity Funds，NRA的interest-related dividends不是一回事。这个应该是RA和NRA都能用来抵州税的，原因是基金里含有本州的municipal bonds不用给本州交税，和联邦税没关系。
最大的问题是，short-term capital gain distributions有没有混在我说的refund percentage里。首先需要注意，
The table on the pages that follow provides the percentage of the withholding on distributions that
qualified as interest-related dividends or short-term capital gain dividends from each of your Fidelity funds.
表里有个Distribution Type，有两种：Dividend和S.T. Cap. Gain。但是问题是，存不存在以下的一一对应：
distribution type Dividends - interest-related dividends
distribution type S.T. Cap. Gain - short-term capital gain dividends
于是我去问Fidelity客服。
我：
In the table, does the percentage shown in a “Dividend” distribution contain any short-term capital gain-related dividends? Does the percentage shown in a “S.T. Cap.Gain” distribution contain any interest-related dividends?
客服（secure message）：
After reviewing the situation, I found that the document has provided all necessary information for reporting your taxes. It lists all the short term gains that each fund paid out and provides a potential tax exemption percentage. This number is potential and not set in stone because each person’s situation is different. We are unable to interpret the document further for you. If you have more questions, I encourage you to speak to a tax professional.
