XSLT: Loop through elements, displaying header when attribute value changes

My XML:

<?xml version="1.0" encoding="utf-8" ?>
<PhoneBill>
    <CallDetails>
        <Call type="Local" date="01-Jan-2001" destination="Brisbane" numberDialed="0755557896" duration="1:53" rate="Flat" charge="0.23"></Call>
        <Call type="Local" date="02-Jan-2001" destination="Brisbane" numberDialed="0755557896" duration="0:42" rate="Flat" charge="0.23"></Call>
        <Call type="Local" date="02-Jan-2001" destination="Brisbane" numberDialed="0755551234" duration="8:65" rate="Flat" charge="0.23"></Call>
        <Call type="Local" date="05-Feb-2001" destination="Brisbane" numberDialed="0755557896" duration="1:02" rate="Flat" charge="0.23"></Call>
        <Call type="Local" date="02-Mar-2001" destination="Brisbane" numberDialed="0755551265" duration="0:10" rate="Flat" charge="0.23"></Call>
        <Call type="International" date="02-Mar-2001" destination="Somewhere" numberDialed="41117555126" duration="0:10" rate="Flat" charge="0.23"></Call>
        <Call type="International" date="03-Mar-2001" destination="Somewhere" numberDialed="41117555126" duration="0:10" rate="Flat" charge="0.23"></Call>
        <Call type="International" date="04-Mar-2001" destination="Somewhere" numberDialed="41117555126" duration="0:10" rate="Flat" charge="0.23"></Call>
        <Call type="International" date="05-Mar-2001" destination="Somewhere" numberDialed="41117555126" duration="0:10" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="02-Jun-2001" destination="National" numberDialed="0455551243" duration="0:10" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="02-Feb-2001" destination="National" numberDialed="0455551254" duration="0:14" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="03-Feb-2001" destination="National" numberDialed="0455551265" duration="0:19" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="06-Feb-2001" destination="National" numberDialed="0455551263" duration="5:21" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="08-Feb-2001" destination="National" numberDialed="0455551265" duration="0:23" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="12-Feb-2001" destination="National" numberDialed="0455551265" duration="3:11" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="27-Feb-2001" destination="National" numberDialed="0455551234" duration="0:20" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="12-Mar-2001" destination="National" numberDialed="0455551265" duration="0:14" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="22-Mar-2001" destination="National" numberDialed="0455551234" duration="0:16" rate="Flat" charge="0.23"></Call>
        <Call type="Mobile" date="26-Mar-2001" destination="National" numberDialed="0455551265" duration="1:13" rate="Flat" charge="0.23"></Call>
    </CallDetails>
</PhoneBill>

I want to have a XSLT file that will provide output for each Call, but display a header for each group of unique @type and also a count of calls per @type and sum() of @charges for that group.

Required output (I haven't bothered including the <tr> and <td> tags:

<b>Local Calls</b>
<p>
Date            Destination  Number Dialed  Duration  Rate  Charge
</p>
<p>
01-Jan-2001 Brisbane     0755557896      1:53       Flat    $0.23
02-Jan-2001 Brisbane     0755557896      0:42       Flat    $0.23
02-Jan-2001 Brisbane     0755557896      8:65       Flat    $0.23
05-Feb-2001 Brisbane     0755557896      1:02       Flat    $0.23
02-Mar-2001 Brisbane     0755557896      0:10       Flat    $0.23
</p>
<p>
Number Local Calls:  5
Total Local Charges:  $1.15
</p>
<b>International Calls</b>
<p>
Date            Destination  Number Dialed  Duration  Rate  Charge
</p>
<p>
01-Jan-2001 Somewhere     41117555126      1:53       Flat    $0.23
02-Jan-2001 Somewhere     41117555126      0:42       Flat    $0.23
02-Jan-2001 Somewhere     41117555126      8:65       Flat    $0.23
05-Feb-2001 Somewhere     41117555126      1:02       Flat    $0.23
</p>
<p>
Number Local Calls:  4
Total Local Charges:  $1.15
</p>

--------------

and so on....

My XLST file thus far is:

<?xml version="1.0" encoding="UTF-8" ?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:output method="html" doctype-public="-//W3C//DTD HTML 4.0 Transitional//EN"/>
    <xsl:template match="//PhoneBill">
        <html>
            <head>
            </head>
            <body>
                <font face="arial" size="2">
                    <xsl:for-each select="CallDetails/Call">
                        <h3><xsl:value-of select="."/> Calls</h3>
                        <p>
                        Date: <xsl:value-of select="/./@date"/><br />
                        Destination: <xsl:value-of select="//./@date"/><br />
                        Number Dialed: <xsl:value-of select="//./@numberDialed"/><br />
                        Duration: <xsl:value-of select="//./@duration"/><br />
                        Rate: <xsl:value-of select="//./@rate"/><br />
                        Charge: $<xsl:value-of select="//./@charge"/>
                        </p>
                        <b>
                            Number of calls: <xsl:value-of select="count(.)"/><br />
                            Total Charges: $<xsl:value-of select="sum(./@charge)"/>
                        </b>
                    </xsl:for-each>
                </font>
            </body>
        </html>
    </xsl:template>
</xsl:stylesheet>

I had intended to next another for-each statement to display each Call, but the concept isn't working as I had expected.  I had initially tried to have the outer for-each condition to be "CallDetails/Call/@type" in the hope that would determine when the @type attribute value changed, but not so.

Could you please provide XSLT code to output what I'm after or, if the XML format has to be changed to rather have child nodes for each value rather than attributes, please let me know.  <-- I was thinking that maybe by using nodes, I could use preceding-sibling, etc to reference the correct values.

This is my second day having a crack at XSLT and am running out of hair to pull out!  :)