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:
Ramon MIRO MARTINEZ, Plaintiff, Appellant, v. COMPANIA TRASATLANTICA ESPANOLA, S.A., et al., Defendants and Third Party Plaintiffs, Appellees, v. INTERNATIONAL SHIPPING AGENCY, Third Party Defendant, Appellee.
No. 80-1548.
United States Court of Appeals, First Circuit.
Argued Feb. 3, 1981.
Decided March 13, 1981.
Carmen F. Arrieta Gimenez, Puerto Nuevo, P. R., with whom Arrieta & Vizcarrondo, Puerto Nuevo, P. R., was on brief, for plaintiff, appellant.
Jorge Bermudez Torregrosa, Hato Rey, P. R., with whom Hartzell, Ydrach, Mellado, Santiago & Perez, Hato Rey, P. R., was on brief, for appellee Compañía Trasatlántica Española.
Alex Gonzalez, San Juan, P. R., with whom Dubon, Gonzalez & Vazquez, San Juan, P. R., was on brief, for third party defendant, appellee International Shipping Agency.
Before CAMPBELL, BOWNES and BREYER, Circuit Judges.
PER CURIAM.
Plaintiff worked as a longshoreman for an independent stevedoring contractor. He was injured while working on defendant’s vessel. The stevedoring contractor was insured under Puerto Rico’s workmen’s compensation law, 11 L.P.R.A. § 1 et seq., and the district court found that plaintiff “received benefits thereunder on account of the injuries sustained”. Plaintiff then brought suit against the shipowner and its insurer, alleging unseaworthiness and negligence.
It is clear under Puerto Rico law that once an employer insures his workmen under the Puerto Rico workmen’s compensation system that remedy is exclusive; the employee has no other remedy against his employer. 11 L.P.R.A. § 21. In 1970 this court held that a shipowner was not an “employer”, within the meaning of the workmen’s compensation statute, of one who works for an insured independent contractor; thus, the shipowner could be sued. Colon Nunez v. Horn-Linie, 423 F.2d 952 (1st Cir. 1970). In 1977, however, the Puerto Rico Supreme Court, in a persuasive opinion, Lugo Sanchez v. Puerto Rico Water Resources Authority, 105 D.P.R. 861 (1977), ruled that we had erroneously interpreted Puerto Rico law. It held that the Puerto Rico statute was not intended to deprive the shipowner (or prime contractor) of his immunity simply because he successfully encourages his independent contractor to pay the workmen’s compensation premium. Thus, whether or not the longshoreman is technically employed by an independent contractor, the shipowner (or prime contractor) is also an “employer” within the terms of the workmen’s compensation law, and its “exclusive remedy” provision applies to him as well. We followed this decision in the later case of Alonso Garcia v. Friesecke, 597 F.2d 284 (1st Cir.), cert. denied, 444 U.S. 940, 100 S.Ct. 292, 62 L.Ed.2d 306 (1979) — a decision identical in all material respects to this one. We held that an injured longshoreman, working for an independent contractor insured under Puerto Rico’s workmen’s compensation law, cannot sue the owner of the vessel.
Plaintiff agrees that if Lugo Sanchez governs this case, his action must be dismissed. He argues, however, that since his claim was pending in court when that case was decided, he should be allowed to recover; in his view Lugo Sanchez should be applied only prospectively. The question of prospective application of a Commonwealth decision is itself a matter of Commonwealth law. See, e. g., Samuels v. Doctors Hospital, Inc., 588 F.2d 485, 488-89 (5th Cir. 1979).
We find no indication that Lugo Sanchez was meant to apply only prospectively. For one thing, the Puerto Rico Supreme Court in Lugo Sanchez itself obviously applied the rule to- events that took place before the case was decided. For another thing, federal district courts in Puerto Rico, whose opinions on matters of Puerto Rico law are entitled to considerable weight, have applied Lugo Sanchez retroactively. See, e. g., Emilio Vera Rodriguez v. Hamburg Amerika Linie, Civil No. 75-1301 (D.P.R.1980). We too applied the rule of Lugo Sanchez retroactively in Friesecke. Moreover, it is normal practice for rules of decision in cases to apply retroactively. Prospective application is reserved for unusual cases where a significant change in the law is accompanied by administrative considerations or unusual reliance upon the prior law which make retroactive application impractical or unjust. See Chevron Oil Co. v. Huson, 404 U.S. 97, 105-09, 92 S.Ct. 349, 354-57, 30 L.Ed.2d 296 (1971); Aufiero v. Clarke, 639 F.2d 49 (1st Cir. 1981). No such considerations militate against retroactive application here. There is no reason to believe that plaintiff, or others in similar circumstances, would have acted differently had the rule in Lugo Sanchez always been the law. Plaintiff argues that Lugo Sanchez deprives him of what he previously believed to be his rights. But such is always true as to one side or the other whenever a case changes what was formerly considered to be the law. We therefore agree with the district court that Lugo Sanchez applies retroactively and bars plaintiff’s action.
Affirmed.
. E. g., Gual Morales v. Hernandez Vega, 604 F.2d 730, 732 (1st Cir. 1979).

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

Choices:

Answer: 1