var my_portal = Portal("https://www.arcgis.com/");

// Step 1: get the FMT table as a FeatureSet
var FMT = FeatureSetByPortalItem(
    my_portal,
    "<item id>",
    11,
    ["*"],
    false
);

// Step 2: Group FMT by fmt_id and sum the budget
var FMT_Grouped = GroupBy(
    FMT,
    ['fmt_FY'],
    [
        { name: 'FMT_Totals',
        expression: 'fmt_budget',
        statistic: 'SUM'
        }
    ]
);

// Step 3: get the MPF table as a FeatureSet
var MPF = FeatureSetByPortalItem(
    my_portal,
    "<item id>",
    2,
    ["mpf_p_mp_prj_id","mpf_fund_id","mpf_fund_amount"],
    false   
);

// Step 4: Group MPF by mpf_fund_id and sum the budget
var MPF_Grouped = GroupBy(
    MPF,
    ['mpf_fund_id'],
    [
        { name: 'MPF_Totals',
        expression: 'mpf_fund_amount',
        statistic: 'SUM'
        }
    ]
);

//Step 5: create a dictionary to store the values
var combinedDict = {
    fields: [
      { name: "FY", type: "esriFieldTypeString" },
      { name: "FMT_Budget", type: "esriFieldTypeDouble" }
	{ name: "MPF_Budget", type: "esriFieldTypeDouble" }
    ],
    geometryType: "",
    features: [],
};

//Step 6: iterate through the Grouped feature sets and add to dictionary
var i = 0;

for (var cur_f_FY in FMT_Grouped) {
	var FMT_FY = cur_f_FY["fmt_FY"]
	var FMT_B = cur_f_FY["FMT_Totals"]
	for (var cur_m_FY in MPF_Grouped) {
		var MPF_FY = Concatenate("FY",Right(cur_m_FY['mpf_fund_id'],2))
 		Filter(MPF_Grouped, "MPF_FY = '" + FMT_FY + "'")){
	combinedDict.features[i++] = {
      	attributes: {
            	FY: Concatenate("FY",Right(f['fmt_id'],2)),
            	FMT_Budget: f['FMT_Totals'],
        }
    }
}

//Step 7: return the dictionary as a Feature Set
return FeatureSet(Text(combinedDict));