24 ANDREJEVA v. LATVIA JUDGMENT 63. In those circumstances, the applicant submitted that the distinction made by the Latvian authorities amounted to discrimination prohibited by Article 14 of the Convention. It had caused her a substantial loss since it had deprived her, as a “non-citizen”, of her pension in respect of seventeen years of employment. The applicant noted in this connection that the retirement pension was her only steady source of income. Admittedly, she also received a medical-treatment allowance and a housing allowance, but she was not able to decide freely how to spend those allowances, and they covered only an insignificant part of her expenses. 64. The applicant acknowledged that, under the Citizenship Act as currently applicable, she was entitled to apply for naturalisation, and that if she became a Latvian citizen she would receive a pension in respect of her entire professional career. However, in her opinion the naturalisation requirements in Latvia were too strict – especially for elderly persons – and had already been severely criticised by the Council of Europe’s Parliamentary Assembly and Commissioner for Human Rights. In any event, the fact that the applicant had freely chosen not to take Latvian citizenship was not decisive in her case; although her status as a “permanently resident non-citizen” was not a special type of Latvian nationality, the rights and obligations attached to that status were evidence of the legal ties between the persons concerned and the Latvian State. 65. Lastly, the applicant was not persuaded by the Government’s argument that the reckoning of periods of employment prior to 1991 was a matter to be addressed by means of international social security agreements. Even if the agreement with the Russian Federation – which had been the subject of intergovernmental negotiations for more than a decade – came into force, it would ultimately still be Latvia’s responsibility to pay the relevant portion of her pension. She further reiterated that there was no legal basis for Russia and Ukraine to provide her with a pension, since her entire working life had been spent in the territory of Latvia. 2. The Government 66. The Government submitted that Article 1 of Protocol No. 1 was not applicable to the pension calculated in respect of the period prior to 1991. In that connection, they referred to and endorsed the reasons given by the Constitutional Court in its judgment of 26 June 2001 (see paragraph 37 above). They emphasised the need to make a clear distinction between the system of retirement pensions that had existed before 1 January 1991 and the system introduced after that date. The current pension system was based on the contributory approach, reflecting the principle of individual contributions. Each person’s contributions thus formed a specified share of the pension fund, and the precise amount of that share could be determined at any time. All contributors therefore had a sufficiently tangible entitlement