What follows is an opinion from a United States Court of Appeals.
Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
In some cases there is some confusion over who should be listed as the appellant and who as the respondent. This confusion is primarily the result of the presence of multiple docket numbers consolidated into a single appeal that is disposed of by a single opinion. Most frequently, this occurs when there are cross appeals and/or when one litigant sued (or was sued by) multiple litigants that were originally filed in district court as separate actions. The coding rule followed in such cases should be to go strictly by the designation provided in the title of the case. The first person listed in the title as the appellant should be coded as the appellant even if they subsequently appeared in a second docket number as the respondent and regardless of who was characterized as the appellant in the opinion.
To clarify the coding conventions, consider the following hypothetical case in which the US Justice Department sues a labor union to strike down a racially discriminatory seniority system and the corporation (siding with the position of its union) simultaneously sues the government to get an injunction to block enforcement of the relevant civil rights law. From a district court decision that consolidated the two suits and declared the seniority system illegal but refused to impose financial penalties on the union, the corporation appeals and the government and union file cross appeals from the decision in the suit brought by the government. Assume the case was listed in the Federal Reporter as follows:
United States of America,
Plaintiff, Appellant
v
International Brotherhood of Widget Workers,AFL-CIO
Defendant, Appellee.
International Brotherhood of Widget Workers,AFL-CIO
Defendants, Cross-appellants
v
United States of America.
Widgets, Inc. & Susan Kuersten Sheehan, President & Chairman
of the Board
Plaintiff, Appellants,
v
United States of America,
Defendant, Appellee.
This case should be coded as follows:Appellant = United States, Respondents = International Brotherhood of Widget Workers Widgets, Inc., Total number of appellants = 1, Number of appellants that fall into the category "the federal government, its agencies, and officials" = 1, Total number of respondents = 3, Number of respondents that fall into the category "private business and its executives" = 2, Number of respondents that fall into the category "groups and associations" = 1.
Note that if an individual is listed by name, but their appearance in the case is as a government official, then they should be counted as a government rather than as a private person. For example, in the case "Billy Jones & Alfredo Ruiz v Joe Smith" where Smith is a state prisoner who brought a civil rights suit against two of the wardens in the prison (Jones & Ruiz), the following values should be coded: number of appellants that fall into the category "natural persons" =0 and number that fall into the category "state governments, their agencies, and officials" =2. A similar logic should be applied to businesses and associations. Officers of a company or association whose role in the case is as a representative of their company or association should be coded as being a business or association rather than as a natural person. However, employees of a business or a government who are suing their employer should be coded as natural persons. Likewise, employees who are charged with criminal conduct for action that was contrary to the company policies should be considered natural persons.
If the title of a case listed a corporation by name and then listed the names of two individuals that the opinion indicated were top officers of the same corporation as the appellants, then the number of appellants should be coded as three and all three were coded as a business (with the identical detailed code). Similar logic should be applied when government officials or officers of an association were listed by name.
Your specific task is to determine the total number of appellants in the case that fall into the category "natural persons". If the total number cannot be determined (e.g., if the appellant is listed as "Smith, et. al." and the opinion does not specify who is included in the "et.al."), then answer 99.

Opinion:
HECKMAN & CO., Inc., v. I. S. DAWES & SON CO., Inc.
(Court of Appeals of District of Columbia.
Submitted February 9, 1926.
Decided April 5, 1926.)
No. 4310.
I. Trusts <@=>63% — Purchaser of cider held not entitled to recover of manufacturer, under trust fund theory, portion of purchase price paid by manufacturer under mistaken belief that it was subject to tax, which tax was later refunded (Revenue Act 1918, § 628 [Comp. St. Ann. Supp. 1919, § 6161 i/2d]).
Purchaser of eider from manufacturer, who, due to mistake of law, added 10 per cent, to purchase price and in turn paid 10 per cent, tax under Revenue Act 1918, § 628 (Comp. St. Ann. Supp. 1919, § 6161%d), on refund of such tax to manufacturer, held not entitled to recover amount so refunded from manufacturer-, on theory that it constituted a trust fund.
2. Taxation <@=>538.
Taxes voluntarily paid cannot be recovered back, and payments with knowledge and without compulsion are voluntary.
3. Payment <@=>84(4)— Purchaser of cider held not entitled to recover of manufacturer, as money paid under mistake of law, amount of refunded tax, which was added to purchase price (Revenue Act 1918, § 628 [Comp. St. Ann. Supp. 1919, § 6161 i/2d]).
Purchaser of cider from manufacturer, who through mistake of law added 10 per cent, to selling price and paid 10 per cent, tax under Revenue Act 1918, § 628 (Comp. St. Ann. Supp. 1919, § 6161%d), on refund of such tax to manufacturer, held not entitled to recover it as money paid under a mistake of law.
Appeal from the Supreme Court of the District of Columbia.
Suit by Heckman & Co., Incorporated, against the I. S. Dawes & Son Company, Incorporated. From a decree dismissing the bill, plaintiff appeals.
Affirmed.
Morris Simon, L. Koenigsberger, and Eugene Young, all of Washington, D. C., for appellant.
Levi Cooke and G. R. Beneman, both of Washington, D. C., and William W. Armstrong, of Rochester, N. Y., for appellee.
Before MARTIN, Chief Justice, and ROBB and YAN ORSDEL, Associate Justices.
ROBB, Associate Justice.
Appeal from a decree in the Supreme Court of the District, dismissing plaintiff’s bill, seeking reT covery of money alleged to have been paid under a mistake of law. The averments of the bill are in substance as follows: The Commissioner of Internal Revenue promulgated a regulation construing section 628 of the Revenue Act of 1918 (40 Stat. 1116 [Comp. St. Ann. Supp. 1919, § 6161%d]) as imposing upon manufacturers of eider a tax equal to 10 per cent, of the price for which sold. As such a manufacturer, defendant paid to the United States 10 per cent, of the price for which its cider was sold. Defendant sold a quantity of cider to the plaintiff, and added to the selling price the 10 per cent, thus paid to the United States. In Sterling v. Casey (C. C. A.) 294 F. 426, it was ruled that the act of 1918 did not authorize the imposition of a tax on eider, and this decision was acquiesced in by the Treasury Department. Thereupon defendant sought and obtained a refund of the eider tax paid by it. Plaintiff then unsuccessfully sought a refund from the defendant of the 10 per cent, involved. The bill alleges that the plaintiff “was compelled to pay said tax to the defendant, as otherwise the defendant would not have sold eider to the National Beverage Company [plaintiff], and all other manufacturers took the same position. The National Beverage Company was forced to pay said tax or else to forego dealing in eider, which was a large and profitable portion of its business.” It is further alleged that the money refunded to the defendant “constitutes a trust fund for the benefit of the plaintiff, to the extent that it represents taxes paid by the National Beverage Company to the defendant.”
The defendant, appellee here, contends that no trust relationship has been made to appear; that this merely is an attempt to obtain a decree for the payment of money, and hence that the suit should have been on the law side. Should we remand the case, with permission to transfer it to the law side, the light of plaintiff to recover would depend on the facts here appearing. It is apparent, therefore, that plaintiff’s right of recovery, whether at law or in equity, may be determined now, and unnecessary delay and expense avoided.
The Revenue Act of 1918, as construed by the Treasury Department, imposed a tax on the manufacturer, not the dealer. The defendant, as such manufacturer, paid this tax. In selling to the plaintiff, it added to the selling price the amount of the tax, which plaintiff voluntarily paid in order to continue “dealing in eider, which was a large and profitable portion of its business.” Defendant paid no tax for the plaintiff but for itself. The sale to the plaintiff was not induced by misrepresentation as to law or fact, nor was it the result of undue influence on the one side and undue confidence on the other. The payment of this 10 per cent, by the plaintiff, therefore, was the result of nothing more than a mistake of law, and such a situation presents no ground for equitable relief. Jordan v. Stevens, 51 Me. 78, 81 Am. Dec. 556; Grant v. Giuffrida, 50 App. D. C. 28, 267 F. 330.
It is equally clear from what we have said that the defendant would be in no better position in an action at law, for “the rule is firmly established that taxes voluntarily paid cannot be recovered back, and payments with knowledge and without compulsion are voluntary.” Chesebrough v. United States, 192 U. S. 253, 259, 24 S. Ct. 262, 264 (48 L. Ed. 432); Detroit Edison Co. v. Wyatt (C. C. A.) 293 F. 489. See also, Erkens v. Nicolin, 39 Minn. 461, 45 N. W. 567; Lam-born v. Dickinson County Comrs., 97 U. S. 181, 24 L. Ed. 926. In Kastner v. Duffy-Mott Co., 125 Misc. Rep. 886, 213 N. Y. S. 128, the facts were identical with those here, and the court said:
“Plaintiffs seek in this action to recover from the defendant the amount of the 10 per cent, tax which was included in the price they paid. The tax, however, under the law, was in no event payable by plaintiffs, but only by the manufacturer; that is, the defendant. There was no tax, or claim of tax, against the plaintiffs. The plaintiffs did not pay the money under duress. There was no governmental claim made against the plaintiffs, and the eases cited by the latter, holding the right to recover for a tax paid under the belief that it was valid when in fact it was void, are not in point. The payment was not made under a mistake of fact. Both parties knew of the enactment of the law. The defendant made the purchase price of the eider greater because of its belief that it had to pay the tax to the government; but, nevertheless, the plaintiffs merely paid the price which the defendant demanded for its goods. Plaintiffs make no claim of any agreement that the defendant was to repay the 10 per cent, in the event that the eider should be held not to be taxable. Under such circumstances, the plaintiffs may not recover.”
The decree is affirmed, with costs.
Affirmed.

Question: What is the total number of appellants in the case that fall into the category "natural persons"? Answer with a number.

Choices:

Answer: 0