State responsibility — Claims — Nationality of — Requirement that claim must be continuously owned by national of claimant State — Claim of national company through interest in non — national company — Limitation of award to percentage of national interest in non — national company.

State responsibility — Claims — In general — Valuation of property — Shares — Valuation by reference to total value of assets of company — Use of balance sheet valuations — Conversion of values from foreign currency into national currency — Rate of exchange — Appropriate date — Whether same date appropriate for fixed and current assets.