seo – How to indicate that this is the *highest* rate using json-ld and

I have a web page that lists the banks with the highest saving account rates in the country. I have created some json-ld that lists one of these banks. However, nowhere do I say in the json-ld that this is the highest rate available. Can that type of information be indicated using json-ld and

<script type="application/ld+json">
    "@context": "",
    "@type": "BankAccount",
    "name": "High Interest Savings Account",
    "offers": {
      "@type": "Offer",
      "offeredBy": {
        "@type": "BankOrCreditUnion",
        "@id": "https://banka/en/on-Home",
        "image": "https://banka/en/images/logo.png",
        "name":"Bank A"
    "interestRate": "1.55",
    "areaServed": "Canada (excluding Quebec)"