<?xml version="1.0" encoding="UTF-8"?>
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://www.eurofiling.info/xbrl/arcrole/partial-breakdown" xlink:type="simple" xlink:href="http://www.eurofiling.info/eu/fr/xbrl/ext/model.xsd#partial-breakdown" />
  <link:roleRef roleURI="http://www.bankofengland.co.uk/data/xbrl/c/role/dict/dom/RX/boec_1" xlink:type="simple" xlink:href="hier.xsd#boec_boec_1" />
  <link:calculationLink xlink:role="http://www.bankofengland.co.uk/data/xbrl/c/role/dict/dom/RX/boec_1" xlink:type="extended">
    <link:loc xlink:href="mem.xsd#boec_x0" xlink:label="loc_boec_x0" xlink:type="locator" />
    <link:loc xlink:href="mem.xsd#boec_b1" xlink:label="loc_boec_b1" xlink:type="locator" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.eurofiling.info/xbrl/arcrole/partial-breakdown" order="1.0" xlink:from="loc_boec_x0" xlink:to="loc_boec_b1" weight="1.0" />
    <link:loc xlink:href="mem.xsd#boec_b2" xlink:label="loc_boec_b2" xlink:type="locator" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.eurofiling.info/xbrl/arcrole/partial-breakdown" order="2.0" xlink:from="loc_boec_x0" xlink:to="loc_boec_b2" weight="1.0" />
    <link:loc xlink:href="mem.xsd#boec_b3" xlink:label="loc_boec_b3" xlink:type="locator" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.eurofiling.info/xbrl/arcrole/partial-breakdown" order="3.0" xlink:from="loc_boec_x0" xlink:to="loc_boec_b3" weight="1.0" />
    <link:loc xlink:href="mem.xsd#boec_b4" xlink:label="loc_boec_b4" xlink:type="locator" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.eurofiling.info/xbrl/arcrole/partial-breakdown" order="4.0" xlink:from="loc_boec_x0" xlink:to="loc_boec_b4" weight="1.0" />
    <link:loc xlink:href="mem.xsd#boec_b5" xlink:label="loc_boec_b5" xlink:type="locator" />
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.eurofiling.info/xbrl/arcrole/partial-breakdown" order="5.0" xlink:from="loc_boec_x0" xlink:to="loc_boec_b5" weight="1.0" />
  </link:calculationLink>
</link:linkbase>
